Sublease Agreement, by and between NGM Biopharmaceuticals, Inc. and AMGEN Inc., dated December 11, 2015

Exhibit 10.9

SUBLEASE

THIS SUBLEASE (this “Sublease”) is made and entered into this 11th day of December, 2015 (the “Effective Date”), by and between AMGEN INC., a Delaware Corporation, (“Sublandlord”) and NGM BIOPHARMACEUTICALS, INC., a Delaware corporation (“Subtenant”).

RECITALS

A. Sublandlord’s predecessor-in-interest, Tularik Inc. (“Original Tenant”), entered into that certain Build-to-Suit Lease dated as of December 20, 2001 (the “Original Master Lease”) with HCP BTC, LLC (“Master Landlord”), a Delaware limited liability company, formerly known as Slough BTC, LLC, for the initial lease of three (3) buildings in the Oyster Point center in South San Francisco, California (the “Center”) and rights to lease additional buildings to be constructed in the Center. The Original Master Lease was subsequently amended on numerous occasions to, among other things, lease additional space and buildings located in the Center to Original Tenant or Sublandlord.

B. Sublandlord and Master Landlord entered into that certain Fifth Amendment to Build-to-Suit Lease and Second Amendment to Workletter dated as of June 19, 2006 (the “Master Amendment”), pursuant to which Master Landlord leased to Sublandlord and Sublandlord leased from Master Landlord those certain two (2) buildings in the Center with the addresses of 331 Oyster Point Boulevard, consisting of 128,751 rentable square feet (the “331 Building”), and 333 Oyster Point Boulevard, consisting of 121,706 rentable square feet, as more particularly depicted on Exhibit B attached hereto (the “Premises” or the “333 Building”). The 331 Building and the 333 Building are collectively referred to herein as the “Buildings”. As used herein, the Original Master Lease, as amended by the Master Amendment only shall be referred to as the “Master Lease”, a true and correct copy of which is attached as Exhibit A hereto.

C. Sublandlord and Subtenant now desire to provide for a sublease of the Premises, subject to and conditioned upon the terms and conditions set forth herein.

AGREEMENT

NOW, THEREFORE, in consideration of the recitals set forth above, the agreements set forth below and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Sublandlord and Subtenant hereby agree as follows:

1. Sublease of Premises; Access 24/7. Subject and pursuant to the provisions hereof, Sublandlord subleases to Subtenant, and Subtenant subleases from Sublandlord, the Premises. Sublandlord shall deliver the entire Premises to Subtenant with all the current warm shell improvements identified on Exhibit C attached hereto in good working condition and repair (the “Delivery Condition”) on the date (the “Delivery Date”) that all of the following have been satisfied: (i) this Sublease has been executed and delivered by Sublandlord and Subtenant, (ii) all consents necessary for the effectiveness of this Sublease have been executed and delivered, including, without limitation, any consents required pursuant to the Master Lease, (iii) Subtenant

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has delivered to Sublandlord the Letter of Credit issued by Subtenant’s Bank (as defined in Section 12.1 below) and meeting the criteria set forth in Section 12; and (iv) Subtenant has delivered to Sublandlord written evidence that Subtenant carries the insurance required to be carried as set forth in Section 9.15 of this Sublease. Notwithstanding anything to the contrary contained in this Sublease, in the event that clause (ii) above shall not have been satisfied by the date that is thirty days after the Effective Date (the “Consent Deadline”), for any reason other than a Subtenant Delay (defined below), Subtenant may terminate this Sublease by written notice to Sublandlord delivered within ten (10) business days after the Consent Deadline, Sublandlord shall then return the Letter of Credit and all sums deposited by Subtenant and the parties shall have no further obligations under this Sublease. A “Subtenant Delay” shall mean an actual delay caused or requested by Subtenant or its agents, employees or contractors.

Subject to the terms of the Master Lease, Subtenant shall have access to the Premises 24 hours per day, seven days a week, 52 weeks per year.

2. Term; Rent Commencement Date; Early Access.

2.1 Term; Phased Occupancy. The term (the “Term”) of this Sublease shall commence upon the date (the “Commencement Date”) that this Sublease has been mutually executed and delivered, and all necessary consents to this Sublease have been obtained (including, without limitation any consents required pursuant to the Master Lease) and shall continue until December 31, 2023 (the “Expiration Date”), unless sooner terminated pursuant to the provisions of this Sublease. Although the Subtenant intends to do the initial build-out in both Phases (as defined below) at the same time, Subtenant shall occupy the Premises in two (2) successive phases (each a “Phase” and collectively, the “Phases”). The first such phase (the “First Phase”) shall include approximately 91,238 rentable square feet in the 333 Building, consisting of the entire 1st, 3rd and 4th floors. The second such phase (the “Second Phase”) shall consist of an additional 30,468 rentable square feet on the 2nd Floor of the 333 Building. Both Phases together comprise the entire 333 Building, which is the Premises hereunder. The obligations to pay Rent (as defined in Section 3.3.5 below) for each Phase shall commence upon the respective rent commencement date for such Phase as described in Section 2.2 below, and shall continue throughout the Term. The above measurements were made by Master Landlord’s architect pursuant to Section 1.1(d) of the Original Master Lease, which Section 1.1(d) is incorporated herein by reference solely for purposes of acknowledging how the Premises were measured.

2.2 Rent Commencement. The rent commencement dates for the respective Phases shall be as follows:

2.2.1 First Phase Rent Commencement Date. Subtenant’s Base Rent and Operating Expense obligations with respect to the First Phase shall commence on the earlier to occur of (a) the date Subtenant takes occupancy of and commences to conduct business in any portion of First Phase of the Premises, or (b) July 1, 2016 (such earlier date, the “First Phase Rent Commencement Date”).

2.2.2 Second Phase Rent Commencement Date. Subtenant’s Base Rent and Operating Expense obligations with respect to the Second Phase shall commence on the earlier to occur of (a) the date Subtenant takes occupancy of and commences to conduct business in any portion of the Second Phase of the Premises, or (b) July 1, 2018, the earlier of such dates being herein called the “Second Phase Rent Commencement Date”.

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2.2.3 Delay in Delivery Date. If all consents necessary for the effectiveness of this Sublease have not been executed and delivered by the Consent Deadline, including, without limitation, any consents required pursuant to the Master Lease, and should Subtenant choose not to terminate the lease in accordance with Section 1 herein, then the July 1, 2016 date in Section 2.2.1 and the July 1, 2018 date in Section 2.2.2 above, shall each be extended on a day for day basis for each day of delay past the Consent Deadline.

2.2.4 Sublandlord Delay. Subtenant estimates that it will complete the construction of the Subtenant Improvements (defined in Section 10.4.1) for the entire Premises by October 1, 2016 (the “Estimated Completion Date”). If Subtenant is delayed in completing the Subtenant Improvements beyond the Estimated Completion Date due to a Sublandlord Delay (defined below), the First Phase Rent Commencement Date or the Second Phase Commencement Date (as applicable), shall extend one day for each day of Sublandlord Delay (it being acknowledged that if the Sublandlord Delay actually delays construction of the Subtenant Improvements for both Phases, then both dates shall extend). As used herein, a “Sublandlord Delay” means an actual delay in construction of the Subtenant Improvements caused by (i) Sublandlord’s failure to review and respond to Subtenant’s requests for review and approval of Subtenant’s plans and specifications within the time periods specified for such review and approval in the Subtenant Work Letter (defined in Section 10.4.1 below), (ii) Sublandlord’s failure to deliver the Premises in the Delivery Condition on the Delivery Date, or (iii) other acts or omissions of Sublandlord, which are not cured within two (2) business days of written notice from Subtenant that such acts or omissions are delaying or will delay completion of the Subtenant Improvements. Any delay in completing the Subtenant Improvements caused by Master Landlord shall not be a Sublandlord Delay and shall not result in an adjustment to the Rent Commencement Dates.

2.2.5 Confirmation of Dates. Following the request of either party, the parties agree to execute and deliver a factually-correct written confirmation documenting the Commencement Date, the First Phase Rent Commencement Date, the Second Phase Rent Commencement Date and the Expiration Date.

2.3 Utilities and Maintenance. From and after the Delivery Date, Subtenant shall be solely responsible to obtain and pay for all utilities provided to the Premises. In addition, subject to Sublandlord’s obligations set forth in Section 8 hereof, Subtenant shall be solely responsible for maintenance and repair of the building systems serving the Premises commencing on the Delivery Date, provided, that, Subtenant shall not be obligated to pay its share of Operating Expenses with respect to a given Phase of the Premises until the applicable Rent Commencement Date for such Phase.

3. Rent.

3.1 Base Rent. Commencing on the First Phase Rent Commencement Date, which shall be deemed to be the first day of Month 1 in the table below, Subtenant shall pay as monthly base rent for the Premises (“Base Rent”) an amount equal to the aggregate square footage of all then applicable Phases multiplied by the applicable Base Rental Rate per rentable square foot per month set forth in the following table:

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For the avoidance of doubt, (i) Subtenant’s Base Rent from the First Phase Rent Commencement Date to the Second Phase Rent Commencement date will be calculated based on the measurement of the First Phase portion of the Premises, (ii) Subtenant’s Base Rent from and after the Second Phase Rent Commencement Date will be calculated based on the entire Premises, and (iii) both Phases shall be subject to annual increases in Base Rent coinciding with the anniversary date of the First Phase Rent Commencement Date. Base Rent and additional rent shall be paid to Sublandlord without demand, deduction, set-off or counterclaim, in advance on the first day of each calendar month during the Term of this Sublease, and in the event of a partial rental month, Base Rent shall be prorated on the basis of the number of actual days in such month. All payments due to Sublandlord shall be paid to Sublandlord c/o Amgen Inc., Accounts Payable, PO Box 100909, Pasadena, CA, 91189-0909 or such other address as Sublandlord may specify in a written notice delivered pursuant to Section 10.1, below.

3.2 Base Rent Abatement. Notwithstanding anything to the contrary contained herein and provided that Subtenant faithfully performs all of the terms and conditions of this Sublease, and no default by Subtenant occurs hereunder, Sublandlord hereby agrees that Subtenant shall not be required to pay the monthly installments of Base Rent for the first three (3) full calendar months following the First Phase Rent Commencement Date (the “Abatement Period”). During the Abatement Period, Subtenant shall still be responsible for the payment of all of its other monetary obligations under this Lease, including without limitation, Operating Expenses. In the event of a default by Subtenant under the terms of this Sublease that results in termination of this Sublease in accordance with the terms hereof, Sublandlord shall be entitled to recovery of the then-unamortized portion of the Base Rent that was abated under the provisions of this Section 3.2.

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3.3 Operating Costs And Expenses.

3.3.1 Payment; Annual Statement of Operating Expenses. Commencing on the First Phase Rent Commencement Date and continuing to the Second Phase Rent Commencement Date, Subtenant shall pay to Sublandlord, as additional rent hereunder, 75% (which is agreed to be the percentage of the Premises that Subtenant will occupy during the First Phase) of the Operating Expenses (as defined in Section 9.2 of the Original Master Lease), allocated to the Premises under the Master Lease (including, without limitation, Article 9 of the Original Master Lease and Section 1(e) of the Master Amendment). From and after the Second Phase Rent Commencement Date, Subtenant shall pay to Sublandlord, as additional rent hereunder, all of the Operating Expenses allocated to the Premises under the Master Lease (as amended by the Master Amendment). All Operating Expenses shall be payable in advance on the first day of each calendar month during the Term of this Sublease in accordance with Section 9.3 of the Original Master Lease. Sublandlord shall provide Subtenant with a copy of Master Landlord’s annual statement of Operating Expenses (as applicable to the Premises) promptly after Sublandlord’s receipt of such annual statement. Sublandlord agrees that Subtenant shall be entitled to audit rights with respect to Sublandlord’s books and records relating to the determination and payment of Operating Expenses related to the Premises for the immediately preceding Lease Year. Subject to the Incorporation Provisions (defined below), the provisions of Article 9 of the Original Master Lease (as amended by the Master Amendment) are incorporated herein only to the extent specifically referenced in this Sublease. Further, Subtenant acknowledges and agrees that, although Article 9 of the Original Master Lease is not otherwise specifically incorporated into this Sublease, Article 9 of the Original Master Lease (as amended by Section 1(e) of the Master Amendment) governs and controls for all purposes the determination of Operating Expenses payable by Sublandlord that Sublandlord is passing through to Subtenant in accordance with the terms of this Section 3.3.

3.3.2 Pro-ration. If the Term shall commence on any day other than January 1 or expire or earlier terminate on any date other than December 31, Subtenant’s obligations under Section 3.3.1 for such first or last partial calendar year shall be prorated on the basis of the number of days elapsed during such calendar years in which this Sublease is in effect bears to 365. In the event that the Term shall expire or earlier terminate on any date other than December 31, for purposes of Section 3.3.1, Sublandlord may either reasonably project, as of the date of such expiration or termination, the Operating Expenses for such calendar year and bill Subtenant for Subtenant’s share thereof at any time thereafter or wait until receipt of Master Landlord’s calculation thereof for the entire calendar year in question and bill Subtenant for Subtenant’s share of Subtenant’s share thereof at any time thereafter; provided, however, if Sublandlord reasonably projects the amount of such Operating Expenses, Sublandlord shall reconcile such projection with the actual Operating Expenses due following the receipt of the actual annual statement of Operating Expenses for such calendar year and shall follow the terms of Section 9.4(a) of the Original Master Lease with respect to the amounts owed or to be reimbursed.

If the obligation to pay any component of Rent under this Sublease commences on other than the first day of a calendar month, or if the Term of this Sublease terminates on a day other than the last day of a calendar month, the Rent for such first or last month of the Term shall be prorated based on the number of days during the Term of this Sublease is in effect during such month. If an increase in Rent becomes effective on other than the first day of a calendar month, the Rent payable for month shall be the sum of the two applicable rates, each prorated for the portion of the month during which such rate is in effect.

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3.3.3 Annual Reconciliation; Accounting; Audit Rights. Because the Master Lease provides for the payment by Sublandlord of Operating Expenses on the basis of an estimate thereof, as and when adjustments between estimated and actual Operating Expenses are made under the Master Lease, as applicable, the obligations of Sublandlord and Subtenant hereunder shall be adjusted in a like manner; and if any such adjustment shall occur after the expiration or earlier termination of the Term, then the obligations of Sublandlord and Subtenant under this Section 3 shall survive such expiration or termination. Within thirty (30) days after Sublandlord receives from the Master Landlord the annual statement of actual Operating Expenses incurred by Master Landlord (the “Accounting”), Sublandlord shall provide Subtenant an accounting of the actual Operating Expenses payable with respect to the Premises as reflected in the Accounting. In the event that the Accounting shows that Subtenant paid more or less than the actual Operating Expenses payable by Subtenant hereunder, then Subtenant shall either promptly receive a credit against future Rent (or such amount shall be paid to Subtenant if the Term has expired or been terminated) or shall be required to pay to Sublandlord the deficient amount within thirty (30) days after Subtenant’s receipt of such Accounting.

Sublandlord shall use commercially reasonable efforts to include in the Consent Master Landlord’s agreement that Subtenant may exercise directly the Sublandlord’s rights as Tenant under Section 9.4(b) of the Original Master Lease to examine Master Landlord’s books and records, provided, that, (i) Sublandlord’s rights to audit Operating Expenses under the Master Lease are not affected or limited thereby, and (ii) in no event will Subtenant be entitled to a reduction of Operating Expenses with respect to the Premises if Sublandlord is obligated to pay such Operating Expenses. If Master Landlord does not so agree, then Sublandlord, shall, upon the written request of Subtenant and at Subtenant’s sole cost and expense, exercise such right (subject to, and in accordance with, the terms of the Master Lease), to confirm the accuracy of the Operating Expenses identified in the annual statement provided by Master Landlord as payable with respect to the Premises. In such event, Sublandlord shall promptly deliver the results of such examination to Subtenant, and shall reasonably cooperate with Subtenant and Master Landlord to resolve any outstanding issues or concerns in accordance with the terms of the Master Lease.

Subject to the foregoing, any and all amounts paid by Sublandlord under the Master Lease for Operating Expenses, real estate taxes or assessments, and other charges with respect to the Premises shall be conclusively deemed to be accurate and binding upon Subtenant for purposes of interpretation of this Section 3.

3.3.4 Payment of Extra Charges. In addition to the amounts payable under Section 3.3.1, Subtenant shall pay to Sublandlord within ten (10) days of Subtenant’s receipt of Sublandlord’s written invoice therefor: (i) any charges, costs, fees or expenses for which Sublandlord is separately charged under the Master Lease (and which are not part of Operating Expenses) and which are attributable to the Premises, including, without limitation, personal property taxes and excess electrical consumption charges (if any); (ii) any and all other sums of money (other than those attributable to Operating Expenses and the charges, costs, fees or expenses covered by clause (i) above) which are or may become payable by

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Sublandlord to Master Landlord relating to the Premises; (iii) any real property taxes and assessments related to the Premises that are separately billed to Sublandlord; and (iv) any and all charges of Master Landlord or other amounts payable to Master Landlord under the Master Lease caused by Subtenant’s failure to perform its obligations under this Sublease.

3.3.5 “Rent” Definition. All forms of additional rent and any other amounts payable by Subtenant to Sublandlord shall be payable by Subtenant without notice (except as expressly provided to the contrary herein), demand, deduction, offset or abatement in lawful money of the United States to Sublandlord at such places and to such persons as Sublandlord may direct. All such amounts, together with Base Rent, are collectively referred to herein as “Rent.”

3.3.6 Interest and Late Charges. Subject to the Incorporation Provisions (defined below), Section 3.2 of the Original Master Lease is hereby incorporated by reference. Any interest and late charges accrued under this Section shall be deemed to be additional rent payable hereunder.

3.4 Free Rent Period. As set forth above, Subtenant shall have no obligation to pay Base Rent or Operating Expenses during the period from the Commencement Date to the applicable Rent Commencement Date (the “Free Rent Period”). However, Subtenant shall pay for all utilities provided to the Premises (power, water/sewer service, and gas service, if applicable) in accordance with Article 10 of the Original Master Lease (incorporated herein as set forth below) and, except as specifically set forth in this Section 3.4, all other terms and conditions of this Sublease shall apply and Subtenant shall remain responsible for the payment of all other monetary obligations under the Sublease during the Free Rent Period.

4. Use. Subtenant shall use and occupy the Premises only for the purposes set forth in Section 13.1 of the Original Master Lease and for no other purpose. Without limiting the generality of the foregoing, Subtenant shall comply with all applicable laws, including without limitation, laws governing hazardous materials, in connection with Subtenant’s use and occupancy of the Premises. Further, Subtenant shall comply with all environmental obligations under the Master Lease, including without limitation, obligations relating to decommissioning of laboratories prior to the end of the Term. Notwithstanding the foregoing, Subtenant shall not be responsible for any environmental conditions existing at the Premises in violation of the Master Lease as of the date of this Sublease.

5. Parking.

5.1 Spaces. Subject to the provisions of this Section 5, Subtenant shall have the parking rights as Sublandlord has with respect to the Premises under the Master Lease (the “Parking Spaces”) during the Term, including, without limitation, as set forth in Section 21.20 of the Original Master Lease and Section 1(g) of the Master Amendment. Subject to the Master Lease and Subtenant obtaining Master Landlord’s consent thereto, Subtenant shall be entitled to allocate up to ten (10) of the Parking Spaces allocated to the Premises under the Master Lease to dedicated visitor parking spaces in front of the Premises. Sublandlord shall not take any action to cause Master Landlord to reduce Sublandlord’s parking rights with respect to the Premises under the Master Lease. All Parking Spaces are unassigned and nonexclusive spaces, and

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notwithstanding any provision herein or in the Master Lease to the contrary, shall be provided to Subtenant at no cost or expense, except for expenses included in Operating Expenses pursuant to (i) Section 9.2(a)(vi) of the Master Lease, or (ii) the second to last sentence of Section 9.2(b) of the Master Lease.

5.2 Compliance. Subtenant shall comply (and cause each of its employees, contractors, representatives, and invitees using such privileges to strictly comply) with all rules, regulations and requirements of Master Landlord with respect to use of the Parking Spaces, the Transportation Demand Management Plan (TDMP) and other matters relating thereto.

6. Additional Rights.

6.1 Signage. Subtenant shall have the right to signage as set forth in Section 11.5 of the Original Master Lease on, or otherwise specifically allocated to, the 333 Building. All signage of Subtenant shall (i) be subject to the terms of the Master Lease, Sublandlord’s reasonable approval and Master Landlord’s approval as to design, composition, size and location, and (ii) be undertaken at Subtenant’s sole cost and expense, including, without limitation, all costs of installation, maintenance, repair, restoration and removal. Not by way of limitation of the foregoing, Sublandlord acknowledges that Subtenant desires maximum Building signage and agrees that, so long as (A) such signage is limited to identifying signage with Subtenant’s name and/or logo, and (B) Master Landlord approves such signage, Sublandlord shall approve such signage.

6.2 Generator. Subtenant has informed Sublandlord that Subtenant wishes to use the existing 1 megawatt emergency backup generator (the “Generator”) which is currently in place on a pad adjacent to the 333 Building (the “Generator Area”). Sublandlord agrees that Subtenant shall be entitled to use and operate the Generator to provide emergency backup power to the Premises, so long as Subtenant obtains its own permits to use and operate the Generator (releasing Sublandlord from any liability with respect to the Generator) and complies with the terms of this Section 6.2. The Generator will be delivered to Subtenant in its current “AS IS” condition. Subtenant and its authorized personnel shall further have the right to access the Generator Area for purposes of testing, maintaining, refueling, repairing and operating the Generator, subject to force majeure and in compliance with any Master Landlord rules and regulations. Subject to Sublandlord’s obligations set forth in Section 8 hereof, Subtenant shall maintain and operate the Generator in compliance with all applicable federal, state and local laws, rules and regulations, including, without limitation, obtaining and maintaining at Subtenant’s sole cost and expense all permits, certificates or other authorizations required for operation of the Generator, such as to comply with requirements of applicable zoning restrictions, City and County requirements and regulations of any governing air quality or environmental management district. Subtenant shall be solely responsible to insure that the Generator is operated in compliance with applicable laws, rules and regulations and the terms of the Master Lease and any governing CC&Rs, and to insure that the Generator does not interfere with the business operations or quiet enjoyment of other tenants or occupants of the Center. Without limiting the indemnity set forth in Section 11.2 below, Subtenant hereby indemnifies, defends and hold Sublandlord harmless from and against any costs, losses, damages, liability or harm caused by or resulting from Subtenant’s use and operation of the Generator. Only if required by Master Landlord in accordance with the

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Master Lease, Subtenant shall remove the Generator upon expiration or earlier termination of this Sublease and repair any damage caused by such removal. If required by the terms of applicable laws, rules or regulations, Subtenant will obtain at its cost and deliver to Sublandlord a copy of any closure or similar report issued by any governmental authority with respect to Subtenant’s cessation of use and removal of the Generator.

6.3 Other Permits. Subtenant will be responsible for obtaining its own permits with respect to any new or existing building systems which require permits for operation or occupancy, including without limitation, elevator permits, certificates of occupancy, and fire protection system permits.

7. Broker Commissions. Each party represents and warrants that it has dealt with no broker in connection with this Sublease and the transactions contemplated herein, except that Sublandlord has been represented by Kidder Matthews (“Primary Broker”) and Binswanger (“Co-Broker”), and Subtenant has been represented by Jones Lang LaSalle (“Secondary Broker”). Following full execution and delivery of this Sublease and the Consent, Sublandlord shall pay the commission payable to the Primary Broker as a result of this Sublease (“Commission”) pursuant to the terms of a separate agreement between the Primary Broker and Sublandlord. It is Sublandlord’s and Subtenant’s understanding that the Primary Broker will share the Commission with the Co-Broker and the Secondary Broker pursuant to a separate agreement amongst such brokers. Each party shall indemnify, defend and hold the other party free and harmless from and against any claim, loss, damage, liability, obligation, cost or expense, including attorneys’ fees suffered, incurred or asserted arising from the breach of the representation and warranty set forth in this Section 7. Under no circumstances will the Primary Broker, the Co-Broker, the Secondary Broker, or any other broker or agent be deemed a third party beneficiary of this Sublease.

8. Condition Of Premises. Subject to Sublandlord’s obligation to deliver the Premises to Tenant in the Delivery Condition as set forth above in Section 1, Subtenant has inspected the Premises and all improvements located therein, and has agreed to accept the Premises in their “AS-IS” condition, existing as of the date of this Sublease, and subject to all applicable municipal, county, state and federal laws, ordinances and regulations governing and regulating the use and occupancy of the Premises. Notwithstanding the foregoing, if it is determined that the Premises were not in the Delivery Condition on the Delivery Date, Sublandlord shall, as Subtenant’s sole remedy hereunder, promptly take such steps as are necessary to cause the Premises to be in the Delivery Condition as soon as reasonably possible after receiving notice thereof from Subtenant at no cost to Subtenant (through Operating Expenses or otherwise), provided, that, (i) Subtenant delivers written notice to Sublandlord detailing such deficiency by no later than the date that is five (5) months after the Delivery Date (time being of the essence), (ii) the failure of the Premises to be in the Delivery Condition was not directly caused by work performed or modifications made by Subtenant or its agents, employees or contractors to the Premises., and (iii) the failure of the Premises to be in the Delivery Condition is not due to the failure of the Master Landlord to perform any obligations of Master Landlord under the Master Lease (in which event, Sublandlord’s obligations with respect to such deficiency shall be limited to the obligations set forth in Section 9.1.1 below). The Premises has not undergone inspection by a Certified Access Specialist (CASp).

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9. Master Lease.

9.1 Compliance With The Master Lease. The terms of this Section 9.1 (including, without limitation, subsections 9.1.1, and 9.1.2 below) shall govern incorporation of any provisions into the Sublease and such provisions are collectively referred to herein as the “Incorporation Provisions.” Subtenant shall not cause a breach of the Master Lease, as more particularly set forth in Section 9.1.3 below. Except as otherwise expressly provided hereunder, or as the context of this Sublease directly indicates otherwise, all of the rights and obligations imposed on the “Tenant” under the Master Lease with respect to the Premises are hereby imposed on Subtenant and all of the rights granted to the “Landlord” under the Master Lease with respect to the Premises are hereby granted hereunder to Sublandlord. All of the terms and conditions contained in the Master Lease are incorporated herein, except as specifically provided below, and shall together with the terms and conditions specifically set forth in this Sublease constitute the complete terms and conditions of this Sublease. To the extent the Master Lease terms are incorporated herein, the following defined terms in the Master Lease shall be deemed to have the respective meanings set forth below for purposes of this Sublease:

Subtenant acknowledges that it has read the attached copy of the Master Lease and agrees that this Sublease is in all respects subject and subordinate to any mortgage, deed, deed of trust, ground lease or other instrument now or hereafter encumbering the Premises or the land on which it is located, to the terms and conditions of the Master Lease and to the matters to which the Master Lease, including any amendments thereto, is or shall be subordinate.

Notwithstanding anything to the contrary set forth herein:

9.1.1 Sublandlord Has No Duty to Perform Master Landlord’s Obligations. Sublandlord shall have no duty to perform any obligations of Master Landlord which are, by their nature, the obligation of an owner or manager of real property. For example, Sublandlord shall not be required to (i) provide services, utilities, repairs, maintenance or other tasks which the Master Landlord is required to provide under the Master Lease, (ii)

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construct any improvements, (iii) procure or maintain the insurance which the Master Landlord is required to procure and maintain under the Master Lease, (iv) develop or implement the Transportation Demand Management Plan (as defined in the Master Lease) or perform its related obligations and activities, or (v) provide any non-disturbance protection in connection with any mortgage, deed, deed of trust, ground lease or other instrument now or hereafter encumbering the Premises. The parties contemplate that Master Landlord will perform such obligations under the Master Lease to the extent required therein and in the event of any default or failure of such performance by Master Landlord, Sublandlord agrees that it will, upon written notice from Subtenant detailing the nature of such failure, make demand upon Master Landlord to perform its obligations under the Master Lease and take appropriate action as reasonably requested by Subtenant to enforce the Master Lease. Except as specifically provided in Section 13 below, under no circumstances shall Subtenant be entitled to any free rent period, construction allowance, tenant improvements, or any other such economic incentives provided to Sublandlord as set forth in the Master Lease.

9.1.2 Time Periods for Performance; Approvals by Both Master Landlord and Sublandlord. Whenever any provision of the Master Lease specifies a time period in connection with the performance of any liability or obligation by Subtenant or any notice period or other time condition to the exercise of any right or remedy by Sublandlord hereunder, such time period shall be shortened in each instance by three (3) business days for the purposes of incorporation into this Sublease, but in no case shall such period be less than three (3) days or the actual time period for performance set forth in the Master Lease, if shorter. Any default notice or other notice of any obligations (including any billing or invoice for any rent or any other expense or charge due under the Master Lease) from Master Landlord which is received by Subtenant (whether directly or as a result of being forwarded by Sublandlord) shall constitute such notice from Sublandlord to Subtenant under this Sublease without the need for any additional notice from Sublandlord. Whenever any provision of the Master Lease requires Subtenant to pay the costs and expenses of “Landlord,” Subtenant shall pay both the costs and expenses of Master Landlord and the reasonable costs and expenses of Sublandlord, unless such costs and expenses are incurred as a result of a breach of the Master Lease or this Sublease by Sublandlord, and such breach or default was not caused by Subtenant. Whenever any provision of the Master Lease requires Subtenant to submit evidence, certificates or other documents or materials, Subtenant shall submit such items to both Sublandlord and Master Landlord, and whenever any provision of the Master Lease requires Subtenant to obtain the approval or consent of “Landlord,” Subtenant shall be required to obtain the approval or consent of both Sublandlord and Master Landlord. In the event of a conflict between the express provisions of this Sublease and the incorporated provisions of the Master Lease, as between Sublandlord and Subtenant, the express provisions of this Sublease shall control.

9.1.3 Subtenant Shall Not Cause a Breach of Master Lease. Subtenant shall not do, permit or suffer any act, occurrence or omission which if done, permitted or suffered by Sublandlord would be (with notice, the passage of time or both) in violation of or a default by the “Tenant” under the Master Lease or could lead in any respect to the termination of the Master Lease. If Subtenant shall default in the performance of any of its obligations under this Sublease, other than its obligation to pay rent to Sublandlord, Sublandlord, without being under any obligation to do so and without thereby waiving such default, may remedy such default for the

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account and at the expense of Subtenant, without notice in a case of emergency and, in all other cases, if the default continues after five (5) business days from the date of written notice thereof from Sublandlord. Subtenant shall defend, indemnify and hold Sublandlord harmless from all claims, costs and liabilities, including reasonable attorneys’ fees and costs, arising out of or in connection with any acts or failures to act by Subtenant, or its agents, employees or contractors that causes Sublandlord to be in a default under the Master Lease or otherwise increases Sublandlord’s liability or responsibilities under the Master Lease.

9.1.4 Sublandlord Shall Not Cause a Breach of the Master Lease, and Shall Not Extend. So long as Subtenant is not in default under this Sublease beyond the expiration of any applicable notice and cure periods, Sublandlord shall perform all Sublandlord’s covenants, agreements, terms, provisions or conditions set forth in the Master Lease (except to the extent they are the obligation of Subtenant hereunder or are the result of a default by Subtenant hereunder), including without limitation, the payment of rent and all other sums payable by Sublandlord thereunder. Sublandlord further agrees that Sublandlord will not exercise any extension options it may have to extend the term of the Master Lease with respect to the 333 Building to enable Subtenant to negotiate a direct lease with Master Landlord, at Subtenant’s election.

9.2 Excluded Provisions. Notwithstanding any provision of this Sublease to the contrary, the following provisions of the Master Lease shall not be incorporated into this Sublease:

Provisions in the Original Master Lease

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Provisions in the Master Amendment

9.3 Inapplicable Amendments. In addition to the foregoing, Sublandlord confirms that the following amendments to the Original Master Lease are inapplicable to the Premises and are not part of the Master Lease for purposes of this Sublease:

(a) First Amendment to Build-to-Suit Lease dated January 22, 2003;

(b) Second Amendment to Build-to-Suit Lease dated March 26, 2004;

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(c) Third Amendment to Build-to-Suit Lease dated August 12, 2004;

(d) Fourth Amendment to Build-to-Suit Lease and First Amendment to Workletter dated June 19, 2006;

(e) Sixth Amendment to Build-to-Suit Lease and Third Amendment to Workletter dated November 21, 2006; and

(f) Seventh Amendment to Build-to-Suit Lease and Fourth Amendment to Workletter dated February 21, 2008.

9.4 Default And/Or Termination Of Master Lease. If for any reason the term of the Master Lease is terminated prior to the Expiration Date of this Sublease, this Sublease shall thereupon terminate and, unless such termination was caused by Sublandlord’s breach of its obligations under Section 9.1.4 above, which was not caused by Subtenant, Sublandlord shall not be liable to Subtenant by reason thereof for damages or otherwise, except that Sublandlord shall return to Subtenant that portion of any rent paid in advance by Subtenant, if any, which is applicable to the period following the date of such termination; provided, however, Sublandlord agrees that so long as Subtenant is not in default after the expiration of applicable notice and cure periods hereunder and except in the event of a casualty or condemnation in which Sublandlord has the right to terminate the Lease, Sublandlord shall have no right to voluntarily terminate the Master Lease with respect to the Premises without Subtenant’s consent, in its sole discretion, unless Master Landlord agrees to recognize this Sublease as a direct agreement with Subtenant upon substantially the same terms set forth in this Sublease, or Subtenant otherwise has the right to continue to occupy the Premises pursuant to a direct agreement with Master Landlord upon terms satisfactory to Subtenant, in its reasonable discretion. Nothing herein shall prevent Sublandlord from terminating the Master Lease with respect to spaces other than the Premises leased by Sublandlord thereunder.

9.5 Holding Over. If Subtenant holds possession of the Premises or any portion thereof after the expiration or earlier termination of this Sublease, then Subtenant shall become a tenant at sufferance only, at a sublease base rental rate equal to one hundred fifty percent (150%) of the Base Rent in effect upon the date of such expiration or termination, plus all additional rent payable by Subtenant hereunder (pro-rated on a daily basis). Acceptance by Sublandlord of rent after such expiration or termination date shall not result in a renewal of this Sublease and shall not waive or modify Sublandlord’s rights to pursue any and all legal remedies available to Sublandlord under applicable law with respect to such holding over by Subtenant. It is acknowledged that if Subtenant holds over after the expiration or earlier termination of this Sublease, Sublandlord may be subject to holdover rent with respect to the Premises under the Master Lease. Accordingly, (i) Sublandlord expressly reserves the right to require Subtenant to surrender possession of the Premises upon the expiration of the Term or upon the earlier termination hereof and the right to assert any remedy at law or in equity to evict Subtenant and/or collect damages in connection with any such holding over, and (ii) Subtenant shall indemnify, defend and hold Sublandlord harmless from and against any and all claims, demands, actions, losses, damages, obligations, costs and expenses, including, without limitation, attorneys’ fees

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incurred or suffered by Sublandlord by reason of Subtenant’s failure to surrender the Premises on the expiration or earlier termination of this Sublease in accordance with the provisions of this Sublease (including, without limitation, the cost of all rent payable by Sublandlord with respect to the Premises under the Master Lease caused by or resulting from Subtenant’s holdover). Notwithstanding the foregoing, Subtenant shall be entitled to make separate arrangements with Master Landlord permitting Subtenant to remain in the Premises after expiration of the Term, provided, that, (a) Sublandlord is released from its obligation to surrender the Premises to Master Landlord under the terms of the Master Lease, and (b) the Master Lease terminates with respect to the Premises for all purposes on the Expiration Date.

9.6 Compliance with Law. Subtenant warrants to Sublandlord that the Subtenant Improvements (as defined below) and any other improvements constructed by Subtenant from time to time shall not violate any applicable law, building code, regulations or ordinance in effect on the applicable Rent Commencement Date or at the time such improvements are placed in service. If it is determined that such warranty has been violated, then Subtenant shall, upon written notice from Sublandlord, promptly correct such violation, at Subtenant’s sole cost and expense Subtenant acknowledges that neither Sublandlord nor any agent of Sublandlord has made any representation or warranty as to the present of future suitability of the Premises for the conduct of Subtenant’s business or proposed business therein.

9.7 Definitions. Subject to the Incorporation Provisions, the definitions of “Improvements” and “Common Areas” set forth in Section 1.1(a) of the Original Master Lease are hereby incorporated by reference.

9.8 Use of Common Areas. Subject to the Incorporation Provisions, Section 1.1(b) of the Original Master Lease is hereby incorporated by reference. Subtenant acknowledges Master Landlord’s reserved rights set forth in Section 1.2 of the Original Master Lease.

9.9 Personal Property. Subject to the Incorporation Provisions, Section 8.1 of the Original Master Lease is hereby incorporated by reference.

9.10 Real Property. Subject to the Incorporation Provisions, Section 8.2 of the Original Master Lease is hereby incorporated by reference.

9.11 Utilities. Subject to the Incorporation Provisions, Sections 10.1 and 10.2 of the Original Master Lease are hereby incorporated by reference; provided however, that the phrases “and, in the case of the Phase II Building, to Tenant’s premises in such Building” and “(or, in the case of the Phase II Building, are not separately metered to Tenant’s premises in that Building)” are hereby deleted in their entirety.

9.12 Alterations; Surrender Obligations; Signs. Subject the Incorporation Provisions, Sections 11.1 through 11.5 of the Original Master Lease are hereby incorporated by reference, except for (i) the last portion of the first sentence in Section 11.1, as amended by Section 1(h) of the Master Amendment (beginning with “except that (i) subject to the final sentence…”) and (ii) the fifth sentence of Section 11.2 (which begins with “Tenant shall also be responsible”). Notwithstanding the foregoing, the language excluded by clause (i) above shall

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not be excluded and shall be deemed to be incorporated into this Sublease, if Master Landlord consents to Subtenant having the rights to perform certain alterations, additions or improvements without consent as set forth therein. Further, notwithstanding anything to the contrary herein, if Subtenant enters into a direct lease of the Premises with the Master Landlord commencing immediately upon termination of the Master Lease and Sublandlord is fully released from any obligations with respect to the surrender condition of the Premises under the Master Lease, Sublandlord agrees that Subtenant shall not be obligated under this Sublease to complete any such removal or restoration.

9.13 Maintenance and Repairs. Subject to the Incorporation Provisions, Section 12.1(a) and Section 12.2 of the Original Master Lease are hereby incorporated by reference, except for the second sentence of Section 12.2(c).

9.14 Use; No Nuisance, Compliance with Laws, Liquidation Sales, & Environmental Matters. Subject to the Incorporation Provisions, Sections 13.1 through 13.6 of the Original Master Lease are hereby incorporated by reference, provided that notwithstanding anything to the contrary contained in this Sublease, under no circumstances shall Subtenant ever have any responsibility for any breach or default of these provisions existing on or prior to the date of this Sublease.

9.15 Insurance. Subject to the Incorporation Provisions, Sections 14.1 through 14.5 of the Original Master Lease and Section 14.7 of the Original Master Lease are hereby incorporated by reference. Without limiting the generality of the foregoing, Subtenant acknowledges and agrees that Subtenant shall carry the same insurance that Sublandlord is obligated to carry under the Original Master Lease, provided, however, that Subtenant shall name Subtenant, Sublandlord and Master Landlord (and any other third parties identified by Sublandlord or Master Landlord in accordance with the terms of the Master Lease) as insureds, additional insureds, or loss payees under such insurance policies as their interests may appear.

9.16 Sublease and Assignment. Subject to the Incorporation Provisions, Article 15, as amended by Section 1(i) of the Master Amendment, is hereby incorporated by reference and shall govern any such assignment or subletting, except as set forth in this Section 9.16. Subtenant shall not voluntarily or involuntarily, by operation of law or otherwise, assign, sublet, mortgage or otherwise encumber all or any portion of its interest in this Sublease or in the Premises without obtaining the prior written consent of Sublandlord and Master Landlord with respect thereto. So long as Master Landlord’s consent is obtained, Sublandlord shall not unreasonably withhold, condition, or delay its consent to any proposed assignment or sublease; provided, however, that Sublandlord or Master Landlord, as the case may be, may require as a condition of granting any such consent that (i) the proposed transferee demonstrate that its financial resources and tangible net worth are at least equal to Subtenant’s financial resources and tangible net worth as of the Effective Date, (ii) the nature of the transferee’s proposed use of the Premises and the transferee’s reputation shall be reasonably satisfactory to Sublandlord and (iii) Subtenant reaffirms, in form satisfactory to Sublandlord, its continuing liability under the Sublease. Notwithstanding the foregoing, Sublandlord confirms that Subtenant is entitled to complete a Permitted Transfer (as defined in Section 15.1 of the Original Master Lease) without Sublandlord’s consent, but with prior or concurrent notice by Subtenant to Sublandlord (a

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“Subtenant Permitted Transfer”). It is acknowledged, however, that, unless and to the extent agreed otherwise in the Consent (defined below) or other separate agreement between Subtenant and Master Landlord, Subtenant shall be required to obtain Master Landlord’s consent to any Subtenant Permitted Transfer. Any assignment, subletting, mortgage or other encumbrance attempted by Subtenant to which Sublandlord and/or Master Landlord has not consented in writing pursuant to the provisions hereof (unless such consent is not required) shall be null and void and of no effect.

9.17 Right of Entry and Quiet Enjoyment. Subject to the Incorporation Provisions, Article 16 of the Original Master Lease is hereby incorporated by reference.

9.18 Casualty and Taking. Subject to the Incorporation Provisions, Article 17 of the Original Master Lease is hereby incorporated by reference, provided, that, Sublandlord shall have no right to terminate this Sublease as a result of damage, destruction or taking, unless (i) such damage, destruction or taking affects the 333 Building, and is of such a magnitude that the Sublandlord has the right to terminate the Master Lease with respect to the 333 Building as a result; or (ii) the damage, destruction or taking (A) affects spaces other than the 333 Building which are leased by Sublandlord under the Master Lease, (B) is of such magnitude that Sublandlord has the right to terminate the Master Lease, and (C) Sublandlord is not entitled to terminate the Master Lease with respect to the affected spaces without also terminating the Lease with respect to the 333 Building.

9.19 Default. Subject to the Incorporation Provisions, Article 18 of the Original Master Lease is hereby incorporated by reference.

9.20 Subordination. Subject to the Incorporation Provisions (except as provided below), Section 19.1 of the Original Master Lease is hereby incorporated by reference, except for the second and parenthetical third sentence. Notwithstanding anything to the contrary in the Incorporation Provisions, it is acknowledged and agreed that references in Section 19.1 of the Original Master Lease to any assignee, ground lessor, mortgagee, trustee, beneficiary or sale/leaseback lessor or other party with an interest in the Buildings, the Property, the Center or any of them, are deemed to be references to Master Landlord’s (as opposed to Sublandlord’s) assignee, ground, lessor, mortgagee, trustee, beneficiary or sale/leaseback lessor.

9.21 Sale of Sublandlord’s Interest. Subject to the Incorporation Provisions, Section 19.2 of the Original Master Lease is hereby incorporated by reference, provided, that, references to “interest in the Buildings and the Property” shall be deemed to be references to “interest in the Master Lease.”

9.22 Estoppel Certificate. Subject to the Incorporation Provisions, Section 19.3 of the Original Master Lease is hereby incorporated by reference, provided, that, notwithstanding anything to the contrary in the Incorporation Provisions, references therein to the term “Landlord” shall be deemed to refer to both Master Landlord and Sublandlord.

9.23 Subordination to CC&Rs. Subject to the Incorporation Provisions, Section 19.4 of the Original Master Lease is hereby incorporated by reference.

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9.24 Mortgagee Protection. Subject to the Incorporation Provisions, Section 19.5 of the Original Master Lease is hereby incorporated by reference, provided that, notwithstanding anything to the contrary in the Incorporation Provisions, references therein to the term “Landlord” shall be deemed to refer to Master Landlord.

9.25 Severability. Subject to the Incorporation Provisions, Section 21.4 of the Original Master Lease is hereby incorporated by reference.

9.26 Surrender; No Merger. Subject to the Incorporation Provisions, Section 21.6 of the Original Master Lease is hereby incorporated by reference.

9.27 Interpretation. Subject to the Incorporation Provisions, Section 21.7 of the Original Master Lease is hereby incorporated by reference.

9.28 No Partnership. Subject to the Incorporation Provisions, Section 21.10 of the Original Master Lease is hereby incorporated by reference.

9.29 Financial Information. Subject to the Incorporation Provisions, Section 21.11 of the Original Master Lease is hereby incorporated by reference.

9.30 Costs. Subject to the Incorporation Provisions, Section 21.12 of the Original Master Lease is hereby incorporated by reference.

9.31 Time. Subject to the Incorporation Provisions, Section 21.13 of the Original Master Lease is hereby incorporated by reference.

9.32 Rules and Regulations. Subject to the Incorporation Provisions, Section 21.14 of the Original Master Lease is hereby incorporated by reference.

9.33 Parking and Traffic. Subject to the Incorporation Provisions, Section 21.20 of the Original Master Lease (as amended by Section 1(g) of the Master Amendment) is hereby incorporated by reference, except for the following provisions which require payment of a monthly fee for parking: (A) the fourth sentence of Section 21.20(b) of the Original Master Lease, which begins with the phrase “The monthly fee”, (B) the last parenthetical sentence of Section 21.20(b) of the Original Master Lease, and (C) clause (ii) of Section 1(g) of the Master Amendment. Without limiting the generality of the Incorporation Provisions, it is acknowledged that the TDMP program and the administration and management thereof are obligations of the Master Landlord and Sublandlord shall have no responsibility with respect thereto.

9.34 Site Plan. Subject to the Incorporation Provisions, the Site Plan attached to the Master Amendment as Exhibit A is hereby incorporated by reference.

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10. Additional Provisions.

10.1 Notices. In the event that Sublandlord or Subtenant shall receive any notice from Master Landlord for any reason pertaining to the Premises (it being agreed that Sublandlord has no obligation to deliver to Subtenant notices under the Master Lease that relate to spaces other than the Premises leased by Sublandlord under the Master Lease), then, within three (3) business days from the date of such receipt, such party shall send a copy of such notice to the other party. All notices, demands, consents and approvals which may or are required to be given by either party to the other hereunder shall be given in the manner provided in Section 21.1 of the Original Master Lease at the addresses shown below (or such other addresses as the parties may designate in writing and delivered in compliance with this Section 10.1). Subject to the Consent, notices to the Master Landlord shall be given in accordance with Section 21.1 of the Master Lease.

10.2 [Intentionally Omitted]

10.3 Test Fits. Subtenant may engage a third party of its choice to develop suggested programming and layouts for Subtenant’s use of the Premises (“Test Fits”). Sublandlord shall contribute up to a maximum of Fifteen Cents ($.15) per rentable square foot of the Premises for the costs of such Test Fits (separate and apart from the Subtenant Improvement Allowance referenced below) (the “Test Fit Allowance”). Sublandlord shall distribute the Test Fit Allowance to Subtenant or Subtenant’s architect upon execution of this Sublease. To the extent the cost of any Test Fits exceed the Test Fit Allowance, such excess costs shall be Subtenant’s sole responsibility, provided, that Subtenant shall be entitled to apply the Subtenant Improvement Allowance to such costs.

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10.4 Subtenant Improvements.

10.4.1 Alterations and Improvements By Subtenant.

(a) Subtenant Improvements. Subtenant shall be entitled to construct tenant improvements in the Premises (the “Subtenant Improvements”), including reasonable security measures for the Premises, subject to and in accordance with the terms of that certain Subtenant Work Letter to be attached to the Consent (which is expressly incorporated herein by this reference) (the “Subtenant Work Letter”) and the terms of the Master Lease and this Sublease. All Subtenant Improvements are subject to the review and approval by Sublandlord and Master Landlord and such processes and procedures as may be required by Master Landlord and will be constructed using Subtenant’s own architects and contractors. In no event will Subtenant proceed with any Subtenant Improvements without first obtaining Sublandlord’s consent (which shall not be unreasonably withheld, conditioned or delayed), as well as Master Landlord’s consent to such Subtenant Improvements pursuant to the terms of the Subtenant Work Letter. As provided in such Subtenant Work Letter, (i) Subtenant shall construct the Subtenant Improvements only after necessary permits, licenses and approvals have been obtained from appropriate governmental agencies; (ii) Subtenant shall construct all Subtenant Improvements in compliance with all relevant codes, laws, rules, regulations, and ordinances and the terms and conditions set forth in the Subtenant Work Letter; (iii) subject to Subtenant’s right to receive the Subtenant Improvement Allowance (as defined and set forth in Section 10.4.2 below), all Subtenant Improvements shall be made at Subtenant’s sole cost and shall be diligently prosecuted to completion; and (iv) Subtenant shall be solely responsible for obtaining a certificate of occupancy or other legal certification such that the Premises can be legally occupied.

(b) No Liens. Should a lien be made or filed against the Premises or real property on which the Premises are situated, Subtenant at its sole cost, shall bond against or discharge said lien within ten (10) business days after Sublandlord’s or Master Landlord’s request to do so.

(c) Incorporation of Master Amendment Provisions. Subject to the Subtenant Work Letter and the Incorporation Provisions, Section 2 of the Master Amendment is hereby incorporated by reference, except for (i) Section 2(a) of the Master Amendment, (ii) Section 2(c) of the Master Amendment, and (iii) Section 2(d) of the Master Amendment.

10.4.2 Subtenant Improvement Allowance. Subtenant shall construct the Subtenant Improvements in accordance with the terms hereof and the Subtenant Work Letter, at Subtenant’s cost, provided, that, Sublandlord shall provide Subtenant with an improvement allowance equal to One Hundred Twenty-Five Dollars ($125.00) per rentable square foot of the Premises (the “Subtenant Improvement Allowance”). Subtenant shall be entitled to apply the Subtenant Improvement Allowance to hard and soft costs incurred by Subtenant to construct the Subtenant Improvements and to prepare for Subtenant’s occupancy to the Premises,

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including, without limitation, all architectural and engineering services, project management, design supervision and construction management fees, moving expenses, costs and expenses to acquire and install security systems, furniture, fixtures and equipment, permitting fees, signage, and data/telephone cabling. Sublandlord confirms that Sublandlord shall not charge Subtenant any construction management or supervision fee which Sublandlord may be charged or may incur (and Sublandlord shall pay any such fees and related costs and expenses charged by Master Landlord). Sublandlord shall disburse the Subtenant Improvement Allowance in accordance with the Disbursement Procedures set forth in Section 10.4.3 below.

10.4.3 Reimbursement Procedure. With respect to Sublandlord’s contribution obligations for the Subtenant Improvement Allowance, Sublandlord shall disburse such payment to Subtenant not more than once per month, within forty-five (45) days after receipt by Sublandlord from Subtenant of: (i) an invoice from Subtenant for such costs; (ii) copies of all underlying invoices showing such costs; (iii) executed contract waivers and/or mechanic’s lien releases with respect to any portion of the Subtenant Improvements then constructed or completed; and (iv) such other information reasonably requested by Sublandlord (the “Disbursement Documentation”). Sublandlord shall be entitled to rely on the accuracy of any and all invoices, fee statements and lien waivers for labor and materials performed on or furnished to the Premises in connection with the Subtenant Improvements and to rely, to the extent submitted, on any and all certifications as to the cost of the improvement submitted by Subtenant’s general contractor or architect. In addition, Sublandlord shall have the option and right to inspect all Subtenant Improvements prior to any disbursement of the Subtenant Improvement Allowance.

10.5 Removal of Personal Property. All articles of personal property, and all business and trade fixtures, machinery and equipment (installed by Subtenant and that can be removed without damage to the Building or negatively impacting Building systems unless Subtenant repairs any such damage or mitigates any negative impact), cabinet work, furniture and movable partitions (collectively, the “Subtenant’s Property’), if any, owned or installed by Subtenant at its expense in the Premises shall be and remain the property of Subtenant and may be removed by Subtenant at any time, provided that Subtenant, at its expense, shall repair any damage to the Premises caused by such removal or by the original installation. Notwithstanding the foregoing, Subtenant acknowledges and agrees that, pursuant to Section 11.3 of the Original Master Lease, removal of any trade fixtures which are affixed to the building or the property or which affect the exterior or structural portions of the Building shall require Master Landlord’s prior written approval; provided, however, should the Consent include a list of trade fixtures which Subtenant shall be allowed to remove from the Premises, then (i) Sublandlord agrees that, subject to the terms of the Consent (and so long as Sublandlord is released by Master Landlord from any obligation or responsibility with respect thereto), it will not have any approval rights in connection therewith, and (ii) Sublandlord shall be deemed to have to consented to the removal of any trade fixtures approved by Master Landlord in accordance with the terms of the Consent. Subtenant shall remove all or any part of the aforementioned property at the expiration or sooner termination of the Sublease and repair any damage caused by such removal and/or installation, all at Subtenant’s expense, and shall otherwise leave the Premises in broom-clean condition in compliance with the terms of Section 12.2(c) of the Original Master Lease. Any articles of personal property, or all business and trade fixtures, machinery and equipment, cabinet work, furniture and movable partitions provided by Sublandlord shall remain the property of Sublandlord, and Subtenant shall not remove any of them from the Premises without the prior written consent of Sublandlord.

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10.6 Waiver. The waiver of either party of any agreement, condition or provision contained herein or any provision incorporated herein by reference shall not be deemed to be a waiver of any subsequent breach of the same or any other agreement, condition or provision, nor shall any custom or practice which may evolve between the parties in the administration of the terms hereof be construed to waive or to lessen the right of a party to insist upon the performance by the other party in strict accordance with said terms. The subsequent acceptance of Rent hereunder by Sublandlord shall not be deemed to be a waiver of any preceding breach by Subtenant of any agreement or condition of this Sublease or the same incorporated herein by reference, other than the failure of Subtenant to pay the particular Rent so accepted, regardless of Sublandlord’s knowledge of such preceding breach at the time of acceptance of such Rent.

10.7 Complete Agreement. Except for the Consent, that certain Confidential Disclosure Agreement by and between Sublandlord and Subtenant dated as of June 23, 2015, this written Sublease, together with all exhibits hereto, contains all the representations and the entire understanding between the parties hereto with respect to the subject matter hereof. There are no oral agreements between Sublandlord and Subtenant affecting this Sublease, and this Sublease supersedes and cancels any and all previous negotiations, arrangements, brochures, agreements and understandings, if any, between Sublandlord and Subtenant or displayed by Sublandlord, its agents or real estate brokers to Subtenant with respect to the subject matter of this Sublease, the Premises or the Building. There are no representations between Sublandlord and Subtenant other than those contained in or incorporated by reference into this Sublease.

11. Indemnification; Exculpation

11.1 Non-Liability Of Sublandlord. Sublandlord shall not be liable to Subtenant, and Subtenant hereby waives and releases all claims against Sublandlord and its partners, officers, directors, employees, trustees, successors, assigns, agents, servants, affiliates, representatives, and contractors (collectively, herein “Sublandlord Affiliates”) for injury or damage to any person or property occurring or incurred in connection with, or in any way relating to, the Premises. Without limiting the foregoing, neither Sublandlord nor any of the Sublandlord Affiliates shall be liable for and there shall be no abatement of Rent for (i) any damage to Subtenant’s property stored with or entrusted to Sublandlord or Sublandlord Affiliates, or (ii) loss of or damage to any property by theft or any other wrongful or illegal act, or (iii) any injury or damage to persons or property resulting from fire, explosion, falling plaster, steam, gas, electricity, water or rain which may leak from any part of the Premises or from the pipes, appliances, appurtenances or plumbing works therein or from the roof, street or sub-surface or from any other place or resulting from dampness or any other cause whatsoever or from the acts or omissions of other sublessees, occupants or other visitors to the Premises or from any other cause whatsoever, or (iv) any latent or other defect in the Premises. Notwithstanding any provision of this Section 11.1 to the contrary, the waivers of liability contained in this Section 11.1 shall not apply to claims for bodily injury or death or damage to property resulting from the gross negligence or willful misconduct of Sublandlord or its agents, employees or contractors, provided, that, any claims with respect to property damage shall be subject to the waiver of subrogation set forth in Section 14.4

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of the Original Master Lease (incorporated herein by Section 9.15) and under no circumstance shall Sublandlord be liable under this Sublease for damage to property in excess of $25,000.00 per occurrence. Notwithstanding anything to the contrary set forth herein or in the Master Lease, in no event shall Sublandlord ever be liable to Subtenant for (and Subtenant hereby waives any right to recover from Sublandlord for) any lost profits, business interruption or any form of consequential, special or punitive damages.

11.2 Indemnification of Sublandlord; Indemnification of Master Landlord. Subtenant shall indemnify, defend, protect and hold Sublandlord, Master Landlord’s managing agent, Master Landlord and their respective members, partners, shareholders, officers, directors, agents, employees and contractors (collectively, the “Indemnified Parties”), harmless from and against any and all liability for all claims, suits, judgments, losses, costs, obligations, damages, expenses, interest and liabilities, including, without limitation, reasonable attorneys’ fees and costs, incurred by Sublandlord or asserted against Sublandlord and arising in connection with (i) this Sublease, the Premises or Subtenant’s activities in or about the Premises (including, without limitation, the use, occupancy and enjoyment of the Property by Subtenant or any invitees, sublessees, licensees, assignees, agents, employees or contractors of Subtenant or holding under Subtenant), or (ii) the act, negligence, fault or omission of Subtenant, its agents, servants, contractors, employees, representatives, licensees or invitees. Notwithstanding any provision of this Section 11.2 to the contrary, the indemnification contained in this Section 11.2 shall not apply to claims resulting from the gross negligence or willful misconduct of the party claiming indemnification or its agents, employees or contractors. Subtenant will give Sublandlord prompt notice of any casualty or accident in, on or about the Premises. The provisions of this Section 11.2 shall survive the expiration or earlier termination of this Sublease.

11.3 Master Landlord Default; Refusal of Consents. Notwithstanding any provision of this Sublease to the contrary, but subject to Sections 9.1.1 and 9.1.3 above, (a) Sublandlord shall not be liable or responsible in any way for any loss, damage, cost, expense, obligation or liability suffered by Subtenant by reason or as the result of any breach, default or failure to perform by the Master Landlord under the Master Lease, including without limitation, in any case where services, utilities, repairs, maintenance or other performance is to be rendered by Master Landlord with respect to the Premises under the Master Lease and Master Landlord either fails to do so or does in an improper, negligent, inadequate or otherwise defective manner, and (b) if Master Landlord refuses to grant Subtenant its consent or approval for any action or circumstances requiring Master Landlord’s approval, Sublandlord shall be released from any obligation to grant its consent or approval with respect thereto.

12. Letter of Credit.

12.1 Letter of Credit Issuance; Amount. Concurrently with Subtenant’s execution of the Sublease, Subtenant shall deliver to Sublandlord, as collateral for the full and faithful performance by Subtenant of all of its obligations under the Sublease and to compensate Sublandlord for all losses and damages Sublandlord may suffer as a result of any default by Subtenant under the Sublease, an irrevocable and unconditional negotiable standby letter of credit (the “Letter of Credit”), in the form attached hereto as Exhibit E and containing the terms required herein, payable in the City of Santa Clara, California, running in favor of

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Sublandlord issued by a solvent, nationally recognized commercial bank that is acceptable to Sublandlord in its sole discretion (the “Bank”) and (1) is chartered under the laws of the United States, any State thereof or the District of Columbia, and which is insured by the Federal Deposit Insurance Corporation; and (2) has a long term rating of BBB or higher as rated by Moody’s Investors Service and/or A or higher as rated by Standard & Poor’s, and Fitch Ratings Ltd., under the supervision of the Superintendent of Banks of the State of California, or a national banking association (collectively, the “Letter of Credit Issuer Requirements”), in the amount of $2,249,126.88 (the “Letter of Credit Amount”). Subject to the terms of Section 12.8 below, Subtenant shall have the right to reduce the Letter of Credit Amount by $374,854.48 on the third (3rd) anniversary of the First Phase Rent Commencement Date, and by another $374,854.48 on the fourth (4th) anniversary of the First Phase Rent Commencement Date.

12.2 Letter of Credit Requirements. The Letter of Credit shall be (i) at sight, irrevocable and unconditional, (ii) maintained in effect, whether through replacement, renewal or extension, for the period from the Sublease Commencement Date and continuing until the date (the “LC Expiration Date”) which is one hundred twenty (120) days after the Expiration Date, and Subtenant shall deliver a new Letter of Credit or certificate of renewal or extension to Sublandlord at least thirty (30) days prior to the expiration of the Letter of Credit then held by Sublandlord, without any action whatsoever on the part of Sublandlord, (iii) subject to “The International Standby Practices ISP98” International Chamber Of Commerce Publication No. 590, (iv) fully assignable by Sublandlord, and (v) permit partial draws. In addition to the foregoing, the form and terms of the Letter of Credit shall provide, among other things, in effect that: (A) Sublandlord shall have the right to draw down an amount up to the face amount of the Letter of Credit upon the presentation to the Bank of Sublandlord’s written statement that (1) Sublandlord is entitled to draw down on the Letter of Credit pursuant to the terms and conditions of this Sublease, and no other document or certification from Sublandlord shall be required other than its written statement to this effect (a “Default Draw”), or (2) Subtenant, as applicant, shall have failed to provide to Sublandlord a new or renewal Letter of Credit satisfying the terms of this Section 12 at least thirty (30) days prior to the expiration of the Letter of Credit then held by Sublandlord, or (3) Subtenant has filed a voluntary petition under the Federal Bankruptcy Code or (4) an involuntary petition has been filed against Subtenant under the Federal Bankruptcy Code; and (B) the Letter of Credit will be honored by the Bank without inquiry as to the accuracy thereof and regardless of whether Subtenant disputes the content of such statement. Sublandlord confirms and agrees that Sublandlord shall only be entitled to make a Default Draw as permitted under Section 12.5.

12.3 Transfer Rights. The Letter of Credit shall also provide that Sublandlord may, at any time and without notice to Subtenant and without first obtaining Subtenant’s consent thereto, transfer all of its interest in and to the Letter of Credit to another party, person or entity, regardless of whether or not such transfer is separate from or as a part of the assignment by Sublandlord of its rights and interests in and to the Sublease. In the event of a transfer of Sublandlord’s interest in the Building, Sublandlord shall transfer the Letter of Credit, in whole (or Subtenant shall, upon Sublandlord’s request, cause a substitute letter of credit to be delivered, as applicable) to the transferee and thereupon Sublandlord shall, without any further agreement between the parties, be released by Subtenant from all liability therefor, and it is agreed that the provisions hereof shall apply to every transfer or assignment of the whole of said Letter of

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Credit to a new Sublandlord. In connection with any such transfer of the Letter of Credit by Sublandlord, Subtenant shall be responsible for paying the Bank’s transfer and processing fees in connection therewith and shall execute and submit to the Bank any applications, documents and instruments as may be necessary to effectuate such transfer.

12.4 Replenishment; Renewal. If, as result of any application or use by Sublandlord of all or any part of the Letter of Credit, the amount of the Letter of Credit shall be less than the Letter of Credit Amount, Subtenant shall, within ten (10) business days thereafter, provide Sublandlord with additional letter(s) of credit in an amount equal to the deficiency (or a replacement letter of credit in the total Letter of Credit Amount), and any such additional (or replacement) letter of credit shall comply with all of the provisions of this Section 12, and if Subtenant fails to comply with the foregoing, notwithstanding anything to the contrary contained in this Sublease, the same shall constitute an incurable default by Subtenant. Subtenant further covenants and warrants that it will neither assign nor encumber the Letter of Credit or any part thereof and that neither Sublandlord nor its successors or assigns will be bound by any such assignment, encumbrance, attempted assignment or attempted encumbrance. Without limiting the generality of the foregoing, if the Letter of Credit expires earlier than the LC Expiration Date, a renewal thereof or substitute letter of credit, as applicable, shall be delivered to Sublandlord not later than thirty (30) days prior to the expiration of the Letter of Credit, which shall be irrevocable and automatically renewable as above provided through the LC Expiration Date upon the same terms as the expiring Letter of Credit or such other terms as may be acceptable to Sublandlord in its sole discretion. However, if the Letter of Credit is not timely renewed or a substitute letter of credit is not timely received, or if Subtenant fails to maintain the Letter of Credit in the amount and in accordance with the terms set forth in this Section 12, Sublandlord shall have the right to present the Letter of Credit to the Bank in accordance with the terms of this Section 12, and the proceeds of the Letter of Credit may be applied by Sublandlord for Subtenant’s failure to fully and faithfully perform all of Subtenant’s obligations under this Sublease and against any Rent payable by Subtenant under this Sublease that is not paid when due and/or to pay for all losses and damages that Sublandlord has suffered or that Sublandlord reasonably estimates that it will suffer as a result of any default by Subtenant under this Sublease. Any unused proceeds shall constitute the property of Sublandlord and need not be segregated from Sublandlord’s other assets. However, Sublandlord agrees to pay to Subtenant within thirty (30) days after the LC Expiration Date the amount of any proceeds of the Letter of Credit received by Sublandlord and not applied against any Rent payable by Subtenant under this Sublease that was not paid when due or used to pay for any losses and/or damages suffered by Sublandlord (or reasonably estimated by Sublandlord that it will suffer; provided that to the extent any estimated expenses are not actually expensed within 90 days after the LC Expiration Date, such amounts shall be returned to Subtenant) as a result of any default by Subtenant under this Sublease; provided, however, that if prior to the LC Expiration Date a voluntary petition is filed by Subtenant, or an involuntary petition is filed against Subtenant by any of Subtenant’s creditors, under the Federal Bankruptcy Code, then Sublandlord shall not be obligated to make such payment in the amount of the unused Letter of Credit proceeds until either all preference issues relating to payments under this Sublease have been resolved in such bankruptcy or reorganization case or such bankruptcy or reorganization case has been dismissed.

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12.5 Security for Subtenant’s Performance. Subtenant hereby acknowledges and agrees that Sublandlord is entering into the Sublease in material reliance upon the ability of Sublandlord to draw upon the Letter of Credit in the event Subtenant fails to fully and faithfully perform all of Subtenant’s obligations under this Sublease and to compensate Sublandlord for all losses and damages Sublandlord may suffer as a result of the occurrence of any default on the part of Subtenant not cured within the applicable cure period under the Sublease. Sublandlord may make a Default Draw (without obligation to do so, and without notice), in part or in whole, only following the occurrence of any default on the part of Subtenant which is not cured within the applicable cure period under the Sublease. Notwithstanding the foregoing, if Sublandlord is prohibited by law from sending Subtenant a default notice, such as due to a bankruptcy stay, Sublandlord shall be entitled to make a Default Draw upon a default by Subtenant with no notice or cure period being required. Subtenant agrees not to interfere in any way with payment to Sublandlord of the proceeds of the Letter of Credit, either prior to or following a “draw” by Sublandlord of any portion of the Letter of Credit, regardless of whether any dispute exists between Subtenant and Sublandlord as to Sublandlord’s right to draw from the Letter of Credit. No condition or term of the Sublease shall be deemed to render the Letter of Credit conditional to justify the issuer of the Letter of Credit in failing to honor a drawing upon such Letter of Credit in a timely manner. Subtenant agrees and acknowledges that Subtenant has no property interest whatsoever in the Letter of Credit or the proceeds thereof and that, in the event Subtenant becomes a debtor under any chapter of the Federal Bankruptcy Code, neither Subtenant, any trustee, nor Subtenant’s bankruptcy estate shall have any right to restrict or limit Sublandlord’s claim and/or rights to the Letter of Credit and/or the proceeds thereof by application of Section 502(b)(6) of the Federal Bankruptcy Code.

12.6 Failure of Letter of Credit Issuer Requirements. Notwithstanding anything to the contrary herein, if at any time the Letter of Credit Issuer Requirements are not met, or if the financial condition of such issuer changes in any other materially adverse way, as determined by Sublandlord in its sole discretion, then Subtenant shall within ten (10) business days of written notice from Sublandlord deliver to Sublandlord a replacement Letter of Credit which otherwise meets the requirements of this Sublease, including without limitation, the Letter of Credit Issuer Requirements. Notwithstanding anything in this Sublease to the contrary, Subtenant’s failure to replace the Letter of Credit and satisfy the Letter of Credit Issuer Requirements within such ten (10) day period Sublandlord shall constitute a material default for which there shall be no notice or grace or cure periods being applicable thereto. In addition and without limiting the generality of the foregoing, if the issuer of any letter of credit held by Sublandlord is insolvent or is placed in receivership or conservatorship by the Federal Deposit Insurance Corporation, or any successor or similar entity, or if a trustee, receiver or liquidator is appointed for the issuer, then, effective as of the date of such occurrence, said Letter of Credit shall be deemed to not meet the requirements of this Section 12, and Subtenant shall within ten (10) business days of written notice from Sublandlord deliver to Sublandlord a replacement Letter of Credit which otherwise meets the requirements of this Section 12 and that meets the Letter of Credit Issuer Requirements (and Subtenant’s failure to do so shall, notwithstanding anything in this Section 12 or the Sublease to the contrary, constitute a material default for while there shall be no notice or grace or cure periods being applicable thereto other than the aforesaid ten (10) business day period).

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12.7 Not a Security Deposit. Sublandlord and Subtenant acknowledge and agree that in no event or circumstance shall the Letter of Credit or any renewal thereof or substitute therefor be (i) deemed to be or treated as a “security deposit” within the meaning of California Civil Code Section 1950.7, (ii) subject to the terms of such Section 1950.7, or (iii) intended to serve as a “security deposit” within the meaning of such Section 1950.7. The parties hereto (A) recite that the Letter of Credit is not intended to serve as a security deposit and such Section 1950.7 and any and all other laws, rules and regulations applicable to security deposits in the commercial context (“Security Deposit Laws”) shall have no applicability or relevancy thereto and (B) waive any and all rights, duties and obligations either party may now or, in the future, will have relating to or arising from the Security Deposit Laws.

12.8 Reduction of Letter of Credit Amount. Subject to the terms of this Section 12.8, Subtenant shall be entitled to a reduction of the face amount of the Letter of Credit (i) by the amount of $374,854.48, effective as of the third (3rd) anniversary of the First Phase Rent Commencement Date; and (ii) by the amount of $374,854.48 effective as of the fourth (4th) anniversary of the First Phase Rent Commencement Date. As a condition to the reduction of the Letter of Credit amount, Subtenant shall not have defaulted beyond any applicable notice and cure period under this Sublease during the 12-month period prior to the reduction date, no uncured breach or default by Subtenant shall then exist under the Sublease and Subtenant has not become a debtor under any chapter of the Federal Bankruptcy Code. Provided that such conditions to reduction are satisfied, Subtenant may cause the Bank to issue a new Letter or Credit or an amendment to the Letter of Credit reflecting the reduced amount, and Sublandlord shall cooperate with such reduction.

13. Abatement for Failure of Services. If and to the extent that Sublandlord receives abatement of the rent or other charges required to be paid by Sublandlord under the Master Lease with respect to the Premises in accordance with Section 10.2 of the Original Master Lease, Sublandlord will abate the same proportion of Subtenant’s Rent hereunder.

14. Miscellaneous.

14.1 Counterparts. This Sublease may be executed in one or more counterparts by the parties hereto. All counterparts shall be construed together and shall constitute one agreement.

14.2 [Intentionally Omitted]

14.3 Modification. This Sublease may not be modified in any respect except by a document in writing executed by both parties hereto or their respective successors.

14.4 Attorneys’ Fees. If either party hereto brings an action or other proceeding against the other to enforce, protect, or establish any right or remedy created under or arising out of this Sublease, the prevailing party shall be entitled to recover from the other party, all costs, fees and expenses, including, without limitation, attorneys’ fees, accounting fees, expenses, and disbursements, incurred or sustained by such prevailing party in connection with such action or proceeding (including, but not limited to, any appellate proceedings relating thereto) or in connection with the enforcement of any judgment or award rendered in such proceeds. The prevailing party’s rights to recover its costs, fees and expenses, and any award thereof, shall be separate from, shall survive, and shall not be merged with any judgment.

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14.5 Binding Effect. This Sublease shall be binding on and inure to the benefit of the parties and their respective heirs, successors and assigns.

14.6 Time Is Of Essence. Time is of essence in respect of each and every term, covenant and condition of this Sublease.

14.7 Governing Law. This Sublease shall be governed by, and construed in accordance with, the laws of the State of California (without giving effect to any choice or conflict of law provision or rule (whether of the State of California or any other jurisdiction) that would cause the application of laws of any jurisdiction other than those of the State of California).

14.8 Representations And Warranties Regarding Authority. Subtenant and Sublandlord hereby represent and warrant to the other party that (i) each person signing this Sublease on their behalf is duly authorized to execute and deliver this Sublease on their behalf, (ii) the execution, delivery and performance of this Sublease has been duly and validly authorized in accordance with the articles of incorporation, bylaws and other organizational documents of such party, (iii) such party is duly organized and in good standing under the laws of their State of incorporation and (iv) upon the execution and delivery of this Sublease, this Sublease shall be binding and enforceable against such party in accordance with its terms.

14.9 Confidentiality. Sublandlord and Subtenant hereby agree that the information contained in this Sublease shall be held in strict confidence and none of the terms or conditions contained herein shall be disclosed to any person or entity, other than Master Landlord and Sublandlord’s and Subtenant’s respective current or prospective attorneys, accountants, consultants, brokers, lenders, investors, acquirers, assignees and subtenants, all of whom (except Master Landlord) shall agree to the confidentiality of this Sublease. Subtenant and its agents shall avoid discussing with, or disclosing to, any third parties (except those specifically listed above) any of the terms, conditions or particulars contained herein. This provision shall not be deemed breached if disclosure is required by applicable law or otherwise consented to in writing by the non-disclosing party.

14.10 Publicity. Subject to the Incorporation Provisions, Section 5 of the Master Amendment is hereby incorporated herein by reference, except for the sixth (6^th) and seventh (7^th) sentences thereof. In addition, Subtenant and Sublandlord each hereby acknowledges and agrees that, except as may be necessary to implement or otherwise effectuate the terms of this Sublease, (i) Subtenant shall not use, without Sublandlord’s prior written approval, which may be withheld in Sublandlord’s sole discretion, the name of Sublandlord, its affiliates, trade names, trademarks or trade dress, products, or any signs, markings, or symbols from which a connection to Sublandlord, in Sublandlord’s absolute and sole discretion, may be reasonably inferred or implied, in any manner whatsoever, including, without limitation, press releases, marketing materials, or advertisements; and (ii) Sublandlord shall not use, without Subtenant’s prior written approval, which may be withheld in Subtenant’s sole discretion, the name of Subtenant, its affiliates, trade names, trademarks or trade dress, products, or any signs, markings, or symbols from which a connection to Subtenant, in Subtenant’s absolute and sole discretion, may be reasonably inferred or implied, in any manner whatsoever, including, without limitation, press releases, marketing materials, or advertisements.

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14.11 Consent of Master Landlord. This Sublease is conditioned upon, and shall not take effect until, receipt of the written consent of the Master Landlord hereto (the “Consent”). Subtenant hereby agrees for the benefit of Sublandlord and Master Landlord (as an express intended third party beneficiary) that (a) other than as expressly and specifically agreed to in writing by Master Landlord, no act, consent, approval or omission of Master Landlord pursuant to this Sublease shall (i) constitute any form of recognition of Subtenant as the direct tenant of Master Landlord, (ii) create any form of contractual duty or obligation on the part of Master Landlord in favor of Subtenant or (iii) waive, affect or prejudice in any way Master Landlord’s right to treat this Sublease and Subtenant’s rights to the Premises as being terminated upon any termination of the Master Lease, and (b) Master Landlord shall have the absolute right to evict Subtenant, and all parties holding under Subtenant, from the Premises upon any termination of the Master Lease. Notwithstanding the foregoing, Sublandlord agrees to request recognition and non-disturbance protection for Subtenant’s benefit from Master Landlord. Further, it is acknowledged that Subtenant may wish to obtain certain additional rights directly from Master Landlord with respect to Subtenant’s use and occupancy of the Premises. Any such agreement with Master Landlord that would bind Sublandlord or otherwise modify or affect Sublandlord’s rights under the Master Lease or this Sublease shall be subject to Sublandlord’s prior written consent.

14.12 Cooperation. Each party shall reasonably cooperate with the other party with respect to seeking any necessary approvals from the Master Landlord, including without limitation approval of this Sublease and the Subtenant Improvements. Subtenant agrees to complete and return any and all forms requested by Sublandlord from time to time for administrative purposes related to the Sublease within five (5) business days of Sublandlord’s written request.

14.13 Anti-Corruption. Neither Subtenant nor any of its directors, officers, employees, or any agent, representative, subcontractor or other third party acting for or on Subtenant’s behalf (collectively, “Representatives”), shall, directly or indirectly, offer, pay, promise to pay, or authorize such offer, promise or payment, of anything of value, to any person, governmental agency, or other entity for the purposes of obtaining any improper advantage in connection with this Sublease. Not by way of limitation of Section 4 of this Sublease, neither Subtenant nor any of its directors, officers or employees shall violate any applicable laws, rules and regulations concerning or relating to public or commercial bribery or corruption (“Anti-Corruption Laws”). Within five (5) business days of Sublandlord’s written request, Subtenant shall execute and deliver a compliance certification (which certification may be limited to Subtenant’s knowledge) with respect to Subtenant’s compliance with Anti-Corruption Laws and this Section 14.13.

14.14 Nonresidential Building Energy Use Disclosure Requirement Compliance. Subtenant hereby acknowledges that Sublandlord may be required to obtain from utility providers and disclose certain information concerning the energy performance of the Premises’ recent historical energy use data pursuant to California Public Resources Code Section 25402.10 and the regulations adopted pursuant thereto (collectively, the “Energy Disclosure

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Requirements”). Sublandlord shall not be liable to Subtenant for the accuracy or content of the information provided by utility providers pursuant to the Energy Disclosure Requirements. Subtenant hereby acknowledges prior receipt of the Data Verification Checklist, as defined in the Energy Disclosure Requirements (the “Energy Disclosure Information”), and agrees that Sublandlord has timely complied in full with Sublandlord’s obligations under the Energy Disclosure Requirements. Subtenant acknowledges and agrees that (i) Sublandlord makes no representation or warranty regarding the energy performance of the Premises or the accuracy or completeness of the Energy Disclosure Information, (ii) the Energy Disclosure Information is for the current condition, occupancy and use of the Premises and that the energy performance of the Premises may vary depending on future condition, occupancy and/or use of the Premises, and (iii) Sublandlord shall have no liability to Subtenant for any errors or omissions in the Energy Disclosure Information. If and to the extent not prohibited by applicable law, Subtenant hereby waives any right Subtenant may have to receive the Energy Disclosure Information, including, without limitation, any right Subtenant may have to terminate the Sublease as a result of Sublandlord’s failure to disclose such information. Further, Subtenant hereby releases Sublandlord from any and all losses, costs, damages, expenses and/or liabilities relating to, arising out of and/or resulting from the Energy Disclosure Requirements, including, without limitation, any liabilities arising as a result of Sublandlord’s failure to disclose the Energy Disclosure Information to Subtenant prior to the execution of this Sublease. Subtenant further acknowledges that pursuant to the Energy Disclosure Requirements, Sublandlord may be required in the future to disclose information concerning Subtenant’s energy usage to certain third parties, including, without limitation, Master Landlord, prospective purchasers, lenders and tenants of the Premises (the “Subtenant Energy Use Disclosure”). Subtenant hereby (A) consents to all such Subtenant Energy Use Disclosures, (B) acknowledges that Sublandlord shall not be required to notify Subtenant of any Subtenant Energy Use Disclosure, and (C) agrees that upon request from Sublandlord, Subtenant shall provide Sublandlord with any energy usage data for the Premises, including, without limitation, copies of utility bills for the Premises. Further, Subtenant hereby releases Sublandlord from any and all losses, costs, damages, expenses and liabilities relating to, arising out of and/or resulting from any Subtenant Energy Use Disclosure.

14.15 Survival. Without limiting survival provisions which would otherwise be implied or construed under applicable law, the provisions of Sections 3.3.3, 6.2, 7, 9.1.3, 9.5, 9.12, 9.14, 9.33, 11.1, 11.2 and 14.14 hereof shall survive the termination of this Sublease with respect to matters occurring or liabilities accruing prior to the expiration of this Sublease.

[remainder of page intentionally left blank; signatures on next page]

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IN WITNESS WHEREOF, the parties hereto have hereunto set their hand on the date first above written.

S-1

EXHIBIT A

MASTER LEASE

[See attached]

A-1

BUILD-TO-SUIT LEASE

THIS BUILD-TO-SUIT LEASE (“Lease”) is made and entered into as of December 20, 2001, by and between SLOUGH BTC, LLC, a Delaware limited liability company (“Landlord”), and TULARIK INC., a Delaware corporation (“Tenant”).

THE PARTIES AGREE AS FOLLOWS:

1. PROPERTY

1.1 Lease of Buildings.

(a) Landlord leases to Tenant and Tenant hires and leases from Landlord, on the terms, covenants and conditions hereinafter set forth, the buildings (individually, a “Building” and collectively, the “Buildings”) to be constructed pursuant to Article 5 hereof and Exhibit C attached hereto on a portion of the real property described in Exhibit A attached hereto (the “Property”), as follows: (i) [REDACTED] (the “Phase IA Building”), to be located on the Property substantially as shown for the building designated “Building A” on the site plan attached hereto as Exhibit B (the “Site Plan”); (ii) [REDACTED] (the “Phase IB Building”), to be located on the Property substantially as shown for the building designated “Building B” on the Site Plan; (iii) [REDACTED] (the “Phase II Building”), to be located on the Property substantially as shown for the building designated “Building E” on the Site Plan; and (iv) subject to final design and to receipt of all required governmental approvals, an enclosed connector bridge connecting the Phase IA Building to the Phase IB Building at the second-story level (the “Connector Bridge”). With respect to the governmental approvals described in clause (iv) of the preceding sentence, Landlord has advised Tenant that the additional square footage created by construction of the Connector Bridge will cause the Project to exceed the maximum square footage amount for which the Project is presently entitled and that, without limiting any other governmental approvals that may be required, a modification of the maximum square footage amount under the existing Project entitlements will therefore be necessary in order to permit construction of the Connector Bridge. Landlord shall pursue diligently and reasonably the design of the Connector Bridge and the securing of all governmental approvals and permits necessary for the construction of the Connector Bridge (other than the interior improvements therein, which shall be Tenant’s responsibility as part of the Tenant Improvements), and Tenant shall cooperate diligently and reasonably with Landlord, in any respects reasonably requested by Landlord, in connection with the design and authorization of the Connector Bridge. For purposes of this Lease, the Connector Bridge shall generally be considered to be a part of the Phase IB Building, and the square footage of the Connector Bridge (which is not presently included in the estimated square footage figure used in this Lease for the Phase IB Building), determined in accordance with Section 1.1(d) of this Lease, shall be included in the square footage of the Phase IB Building for purposes of calculating Tenant’s Minimum Rent, additional rent and Operating Expense obligations with respect to the Phase IB Building and the Tenant Improvement Allowance with respect to the Phase IB Building; provided, however, that the square footage of the Connector Bridge shall not be taken into account in determining the number of parking spaces allocated to Tenant or required to be paid for by Tenant pursuant to Section 21.20(b) of this Lease. All references in this Lease to the Phase II Building as being leased to Tenant hereunder shall be construed to refer solely to the office and laboratory portion of the Phase II Building and not to the ground-floor retail portion of such building. The Phase IA Building and the Phase IB Building (including the Connector Bridge) are sometimes hereinafter collectively referred to as the “Phase I Buildings.” The Property is commonly known as Britannia Oyster Point (the “Center”) and is located at Oyster Point Boulevard and Veterans Boulevard in the City of South San Francisco, County of San Mateo, State of California. The Buildings and the other improvements to be constructed on the Property pursuant to Article 5 hereof and Exhibit C attached hereto are sometimes referred to collectively herein as the “Improvements.” The parking areas, driveways, sidewalks, landscaped areas and other portions of the Center that lie outside the exterior walls of the Buildings and of the other buildings to be constructed in the Center, as depicted on the Site Plan and as hereafter modified by Landlord from time to time in accordance with the provisions of this Lease, are sometimes referred to herein as the “Common Areas.”

(b) As an appurtenance to Tenant’s leasing of the Buildings pursuant to Section 1.1(a), Landlord hereby grants to Tenant, for the benefit of Tenant and its employees, suppliers, shippers, customers and invitees, during the term of this Lease, the non-exclusive right to use, in common with others entitled to such use, (i) those portions of the Common Areas improved from time to time for use as parking areas, driveways, sidewalks, landscaped areas, or for other common purposes, and (ii) all easements, access rights and similar rights and privileges relating to or appurtenant to the Center and created or existing from time to time under any easement agreements, declarations of covenants, conditions and restrictions, or other written agreements now or hereafter of record with respect to the Center, subject however to any limitations applicable to such rights and privileges under applicable law, under this Lease and/or under the written agreements creating such rights and privileges.

(c) Tenant shall be entitled to install, in areas of the Property adjacent to one or more of the Buildings, in what would otherwise constitute Common Areas, at Tenant’s sole expense and for the exclusive use of Tenant and its employees and invitees, subject to all of the conditions set forth in this paragraph (c), (1) a half-court basketball court and (2) an equipment yard. In no event shall Tenant be obligated to pay rent for the use of such areas, nor shall such areas be considered part of the Buildings or premises leased by Tenant for purposes of any calculations of rent or of Tenant’s Operating Cost Share under this Lease, but for all other purposes (including, but not limited to, the purposes specifically identified in this paragraph (c)), such areas shall be considered part of the Buildings leased by Tenant under this Lease. Without limiting the generality of the foregoing, Tenant’s construction and use of such basketball court and equipment yard shall be subject to the following requirements and restrictions: (i) the locations in which such basketball court and equipment yard are to be constructed shall be subject to Landlord’s prior written consent, in Landlord’s sole discretion; (ii) the plans and specifications for construction of all improvements constituting such basketball court and equipment yard shall be subject to Landlord’s prior written consent, in Landlord’s sole discretion, and such improvements shall otherwise be constructed in full compliance with the requirements applicable to Tenant’s Work under Exhibit C attached hereto; (iii) the liability insurance to be carried by Tenant pursuant to Section 14.1(a) of this Lease shall cover, to Landlord’s satisfaction, any claims and liabilities arising out of the use of such basketball court and equipment yard; (iv) Tenant shall ensure that the construction and use of such basketball court and equipment yard do not interfere with the use of any parking or driveway areas on the Property and do not create any visual or noise interference with the use and enjoyment of the Property by the other tenants thereof; (v) Tenant shall be solely responsible for the maintenance and repair of such basketball court and equipment yard, at Tenant’s sole expense, as part of Tenant’s maintenance obligations under Section 12.2 of this Lease; and (vi) Tenant shall take all such steps as Landlord in its reasonable discretion may require in order to restrict access to and use of such basketball court and equipment yard to Tenant’s employees and invitees.

(d) All measurements of building areas under this Lease shall be made by Landlord’s architect in accordance with the same formula applied by Landlord to the building areas for the other leased buildings in the Center, which formula consists of measurement from the exterior faces of exterior walls, from the dripline of any overhangs and, where applicable, from the centerline of any demising walls. In measuring interior space (relevant only to the determination of space actually being used or occupied by Tenant in the Phase II Building during the phase-in of Tenant’s occupancy thereof), measurements involving any demising walls separating space actually used or occupied by Tenant from space not used or occupied by Tenant shall be made to the centerline of the demising wall.

1.2 Landlord’s Reserved Rights. To the extent reasonably necessary to permit Landlord to exercise any rights of Landlord and discharge any obligations of Landlord under this Lease, Landlord shall have, in addition to the right of entry set forth in Section 16.1 hereof, the following rights: (i) to make changes to the Common Areas, including, without limitation, changes in the location, size or shape of any portion of the Common Areas, and to construct and/or relocate parking structures and/or parking spaces in the Center, but not materially decrease the number of parking spaces in the Center; (ii) to close temporarily any of the Common Areas for maintenance or other reasonable purposes, provided that reasonable parking and reasonable access to the Buildings remain available; (iii) to construct, alter or add to other buildings or improvements in the Center; (iv) to build in areas adjacent to the Center and to add

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such areas to the Center; (v) to use the Common Areas while engaged in making additional improvements, repairs or alterations to the Center or any portion thereof; and (vi) to do and perform such other acts with respect to the Common Areas and the Center as may be necessary or appropriate; provided, however, that notwithstanding anything to the contrary in this Section 1.2, Landlord’s exercise of its rights hereunder (x) shall not cause any material diminution of Tenant’s rights, nor any material increase of Tenant’s obligations, under this Lease, and (y) shall be conducted in such a manner as to minimize, to the extent reasonably possible, any adverse effect on Tenant’s business operations in the Buildings (including, but not limited to, reasonable prior notice to Tenant of any pile-driving or other activities of Landlord that will cause significant noise or vibration in the Buildings).

2. TERM

2.1 Term; Rent Commencement Dates. The term of this Lease shall commence upon mutual execution of this Lease by Landlord and Tenant.

(a) Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to the Phase I Buildings shall commence on the earlier to occur of (i) the date which is one hundred eighty (180) days after the date Landlord delivers to Tenant a Structural Completion Certificate for each of the Phase I Buildings (or, if the Structural Completion Certificates for the two Phase I Buildings are delivered on different dates, the date Landlord delivers to Tenant the Structural Completion Certificate for the second of the two Phase I Buildings) pursuant to the Workletter attached hereto as Exhibit C (the “Workletter”), subject to any adjustments in such time period to the extent authorized or required under the provisions of such Workletter, or (ii) the date Tenant takes occupancy of and commences operation of its business in either of the Phase I Buildings, the earlier of such dates being herein called the “Phase I Rent Commencement Date”; provided, however, that in no event shall the Phase I Rent Commencement Date occur earlier than May 1, 2003, unless determined pursuant to clause (ii) of this sentence or unless an earlier date is hereafter mutually agreed upon in writing by Landlord and Tenant; and provided further, however, that if the Phase I Rent Commencement Date is determined pursuant to clause (ii) of this sentence as a result of Tenant’s occupancy of and commencement of business operations in one of the two Phase I Buildings, then notwithstanding any other provisions of this Lease to the contrary, Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to the second of the Phase I Buildings and with respect to the Connector Bridge (regardless of whether the Phase IB Building is the first Phase I Building to be occupied by Tenant) shall not commence until the earlier to occur of the date described in clause (i) of this sentence or the date Tenant takes occupancy of and commences operation of its business in the second Phase I Building. Based on the estimated construction schedules attached hereto as Exhibit D, the parties presently estimate that the Phase I Rent Commencement Date shall occur on May 1, 2003.

(b) Tenant shall be entitled to occupy the Phase II Building in up to four (4) successive phases. The first such phase (“Phase IIA”) shall consist of a minimum of 23,300 square feet of the Phase II Building. The second such phase (“Phase IIB”) shall consist of at least that amount of space which, when added to the Phase IIA space, shall equal a minimum of 46,600 square feet of the Phase II Building. The third such phase (“Phase IIC”) shall consist of at least that amount of space which, when added to the Phase IIA and Phase IIB spaces, shall equal a minimum of 69,900 square feet of the Phase II Building. The fourth such phase (“Phase IID”) shall consist of the remainder, if any, of the non-retail portion of the Phase II Building. As to any of such phases, Tenant shall have the right to take and occupy a larger portion of the Phase II Building than the minimum space required for the applicable phase, in which event the space for the applicable phase shall be deemed to consist of the greater of the minimum required amount of space for such phase or the amount of space actually occupied by Tenant. Tenant shall not be deemed to be occupying any portion of the Phase II Building solely by reason of constructing interior improvements in such portion in connection with Tenant’s intended future use and occupancy of such portion or by reason of maintaining insurance on or performing maintenance or repair work in such portion, but use of any portion of the Phase II Building for any other purpose by Tenant (including, but not limited to, any storage uses other than storage or staging of materials on a temporary basis in the course of construction) shall be deemed to constitute occupancy of such portion by Tenant. At least thirty (30) days prior to the applicable Rent Commencement Date for each phase of Tenant’s occupancy of the Phase II Building as set forth in subparagraphs (i) through (iv) below, Tenant shall notify Landlord in

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writing of the portion of the Phase II Building that Tenant intends to actually use and occupy during such phase. Tenant acknowledges, however, that if Tenant in fact uses a greater portion of the Phase II Building than specified in Tenant’s notice to Landlord with respect to the applicable phase, then Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to Tenant’s occupancy of the Phase II Building during such phase shall be controlled by the amount of space actually used or occupied by Tenant. Landlord shall have the right to inspect the Phase II Building from time to time prior to the Phase IID Rent Commencement Date, on not less than one (I) business day’s prior notice to Tenant, to confirm and measure the amount of space actually being occupied by Tenant in the Phase II Building, and the measurement and calculation of such space actually being occupied by Tenant shall be made by Landlord’s architect as contemplated in Section 1.1(d) of this Lease. On the Phase IIA Rent Commencement Date as hereinafter defined, all of Tenant’s obligations under this Lease shall become applicable and effective in full with respect to all of the Phase II Building, except that the following obligations with respect to each phase of Tenant’s occupancy of the Phase II Building shall become effective only on the respective Rent Commencement Date for such phase: (A) Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to such phase; (B) Tenant’s obligations under Section 8.2 of this Lease with respect to real property taxes and assessments upon Improvements constructed by Landlord and located within such phase; (C) Tenant’s obligation under Section 10.1 of this Lease to pay for utilities or services supplied to or consumed in or with respect to such phase, but only to the extent such utilities or services are consumed by or supplied at the request of Landlord or its agents, employees or contractors and the cost thereof can reasonably be segregated from the cost of utilities or services furnished to the portions of the Phase II Building occupied by Tenant; (D) Tenant’s maintenance and repair obligations under Section 12.2 of this Lease with respect to any Improvements constructed or installed in such phase by Landlord as part of Landlord’s Work under the Workletter, except that Tenant shall be responsible for any such maintenance or repairs required as a result of the negligent or willful acts or omissions of Tenant or its agents, employees, contractors or invitees; and (E) Tenant’s obligation to cause the applicable phase to comply with any applicable Requirements under Section 13.4(a) of this Lease, except to the extent the applicability of such Requirements is triggered by Tenant’s actual use of any portion of the Building or by Tenant’s construction of Improvements in any portion of the Building. The Rent Commencement Dates for the respective phases of the Phase II Building shall be as follows:

(i) Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to Phase IIA shall commence on the earlier to occur of (A) the date which is one hundred eighty (180) days after the date Landlord delivers to Tenant a Structural Completion Certificate for the Phase II Building pursuant to the Workletter, subject to any adjustments in such time period to the extent authorized or required under the provisions of such Workletter, or (B) the date Tenant takes occupancy of and commences operation of its business in any portion of the Phase II Building, the earlier of such dates being herein called the “Phase IIA Rent Commencement Date”; provided, however, that in no event shall the Phase IIA Rent Commencement Date occur earlier than May 1, 2004, unless determined pursuant to clause (B) of this sentence or unless an earlier date is hereafter mutually agreed upon in writing by Landlord and Tenant. Based on the foregoing provisions and on the estimated construction schedules attached hereto as Exhibit D, the parties presently estimate that the Phase IIA Rent Commencement Date shall occur on May 1, 2004.

(ii) Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to Phase IIB shall commence on the earlier to occur of (A) the date which is six (6) months after the Phase IIA Rent Commencement Date (as extended for any Landlord Delays occurring after the Phase IIA Rent Commencement Date in connection with Tenant’s construction of Tenant Improvements in Phase IIB) or (B) the date Tenant takes occupancy of and commences operation of its business in any portion of Phase IIB of the Phase II Building, the earlier of such dates being herein called the “Phase IIB Rent Commencement Date”; provided, however, that in no event shall the Phase IIB Rent Commencement Date occur earlier than November 1, 2004, unless determined pursuant to clause (B) of this sentence or unless an earlier date is hereafter mutually agreed upon in writing by Landlord and Tenant.

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(iii) Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to Phase IIC shall commence on the earlier to occur of (A) the date which is six (6) months after the Phase IIB Rent Commencement Date (as extended for any Landlord Delays occurring after the Phase IIB Rent Commencement Date in connection with Tenant’s construction of Tenant Improvements in Phase IIC) or (B) the date Tenant takes occupancy of and commences operation of its business in any portion of Phase IIC of the Phase II Building, the earlier of such dates being herein called the “Phase IIC Rent Commencement Date”; provided, however, that in no event shall the Phase IIC Rent Commencement Date occur earlier than May 1, 2005, unless determined pursuant to clause (B) of this sentence or unless an earlier date is hereafter mutually agreed upon in writing by Landlord and Tenant.

(iv) Tenant’s Minimum Rental, additional rent and Operating Expense obligations with respect to Phase IID shall commence on the earlier to occur of (A) the date which is six (6) months after the Phase IIC Rent Commencement Date (as extended for any Landlord Delays occurring after the Phase IIC Rent Commencement Date in connection with Tenant’s construction of Tenant Improvements in Phase IID) or (B) the date Tenant takes occupancy of and commences operation of its business in any portion of Phase IID of the Phase II Building, the earlier of such dates being herein called the “Phase IID Rent Commencement Date”; provided, however, that in no event shall the Phase IID Rent Commencement Date occur earlier than November 1, 2005, unless determined pursuant to clause (B) of this sentence or unless an earlier date is hereafter mutually agreed upon in writing by Landlord and Tenant.

(c) Notwithstanding any other provisions of this Section 2.1 or of Section 2.3 below, if Landlord has not delivered a Final Completion Certificate under the Workletter with respect to the Building Shell of a Building or phase of a Building, as applicable, and completed all Building Shell work that must be completed as a condition of delivery of such Final Completion Certificate for the applicable Building or phase, by the date the Rent Commencement Date for such Building or phase would otherwise occur under this Section 2.1, and if the incomplete elements of such Building Shell work materially impair Tenant’s ability to occupy and commence operation of its business in the applicable Building or phase, then the Rent Commencement Date for the applicable Building or phase, to the extent it is determined by the passage of time since delivery of the Structural Completion Certificate and not by actual occupancy, shall be extended, day for day, for a period equal to the lesser of (i) the number of days from the date the Rent Commencement Date for such Building or phase would otherwise have occurred under this Section 2.1 until the date Landlord has completed all Building Shell work that must be completed as a condition of delivery of the Final Completion Certificate for the applicable Building or phase to such an extent that Tenant’s ability to occupy and commence operation of its business in the applicable Building or phase is no longer materially impaired by any remaining incomplete elements of Landlord’s Building Shell work in the applicable Building or phase, or (ii) the number of days by which Landlord’s delay (beyond the date the applicable Rent Commencement Date would otherwise have occurred pursuant to this Section 2.1) in completing all Building Shell work that must be completed as a condition of delivery of the Final Completion Certificate for the applicable Building or phase has actually delayed Tenant’s ability to occupy and commence operation of its business in the applicable Building or phase; provided, however, that the period (if any) for which any Rent Commencement Date is extended pursuant to this paragraph (c) shall be reduced, day for day, for a period equal to the length of any delays in Landlord’s completion of the Building Shell work that must be completed as a condition of delivery of the Final Completion Certificate for the applicable Building or phase to the extent such delays are caused by any Tenant Delays (as defined in the Workletter). Nothing in this paragraph (c) is intended to imply or require that Landlord’s Site Improvements relating to a Building or phase shall be completed by the Rent Commencement Date for such Building or phase; in fact, the parties expressly contemplate that completion of various elements of the Site Improvements may be deferred by Landlord, in its discretion, until after completion of Tenant’s Work under the Workletter in order to avoid the risk of damage to such Site Improvements in the course of Tenant’s Work, and Landlord agrees to complete such Site Improvements with reasonable diligence following completion of Tenant’s Work under the Workletter, subject to the effects of any Tenant Delays and/or Unavoidable Delays (as defined in the Workletter).

(d) The term of this Lease shall end on the day (the “Termination Date”) immediately preceding the fifteenth (15^th) anniversary of the last of the Phase II Rent Commencement Dates to occur, unless sooner terminated or extended as hereinafter provided.

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2.2 Early Possession. Tenant shall have the nonexclusive right to occupy and take possession of the respective Buildings from and after the date of Landlord’s delivery of the Structural Completion Certificate described in the applicable portion of Section 2.1 for the applicable Building, even though Landlord will be continuing to construct the balance of Landlord’s Work as contemplated in the Workletter, for the purpose of constructing Tenant’s Work as contemplated in the Workletter and for the purpose of installing fixtures and furniture, laboratory equipment, computer equipment, telephone equipment, low voltage data wiring and personal property and other similar work related to the construction of Tenant’s Work and/or preparatory to the commencement of Tenant’s business in the applicable Building. Such occupancy and possession, and any early access under the next sentence of this Section 2.2, shall be subject to and upon all of the terms and conditions of this Lease and of the Workletter (including, but not limited to, conditions relating to the maintenance of required insurance), except that Tenant shall have no obligation to pay Minimum Rental or Operating Expenses for any period prior to the applicable Rent Commencement Date as determined under Section 2.1; such early possession shall not advance or otherwise affect the respective Rent Commencement Dates or the Termination Date determined under Section 2.1. Tenant shall also be entitled to have early access to the respective Buildings and the Property at all appropriate times prior to Landlord’s delivery of the Structural Completion Certificate for the applicable Building, subject to the approval of Landlord and its general contractor (which approval shall not be unreasonably withheld or delayed) and to all other provisions of this Section 2.2 and of the Workletter (including, but not limited to, conditions relating to the maintenance of required insurance), solely for the purpose of installing fixtures and equipment and other similar work preparatory to the construction of Tenant’s Work and the commencement of Tenant’s business on the Property, and Tenant shall not be required to pay Minimum Rental or Operating Expenses by reason of such early access until the applicable Rent Commencement Date otherwise occurs; without limiting the generality of the preceding portion of this sentence, Tenant shall be entitled to have early access to the Property and the respective Buildings as soon as the roof metal decking of the applicable Building is in place, to begin hanging electrical, mechanical and plumbing services from the overhead structure, subject to all of the provisions of this Section 2.2.

2.3 Delay In Possession. Landlord agrees to use its best reasonable efforts to complete Landlord’s Work (as defined in the Workletter) promptly, diligently and within the respective time periods set forth in the respective estimated construction schedules attached hereto as Exhibit D and incorporated herein by this reference, as such schedules may be modified from time to time by mutual written agreement of Landlord and Tenant, and subject to any Tenant Delays and Unavoidable Delays (as respectively defined in the Workletter); provided, however, that Landlord shall not be liable for any damages caused by any delay in the completion of such work, nor shall any such delay affect the validity of this Lease or the obligations of Tenant hereunder. Notwithstanding any other provision of this Section 2.3, however, unless Landlord delivers a Structural Completion Certificate for at least one of the two Phase I Buildings and tenders possession of those completed structural portions of the Building Shell for such Building that must be completed as a condition of delivery of the Structural Completion Certificate by the date which is one hundred twenty (120) days after the date specified for structural completion as to such Phase I Building in the applicable Estimated Construction Schedule attached hereto as Exhibit D, Tenant shall have the right to terminate this Lease without further liability hereunder by written notice delivered to Landlord at any time prior to Landlord’s delivery of a Structural Completion Certificate for at least one Phase I Building and tender of possession of the completed structural portions of the Building Shell for such Phase I Building to Tenant; provided, however, that the applicable date on which Tenant’s termination right becomes exercisable pursuant to this sentence shall be extended, day for day, for a period equal to the length of any delays in Landlord’s design and construction of the respective Phase I Building Shells that are caused by any Unavoidable Delays or Tenant Delays (as respectively defined in the Workletter). If such a termination right arises in favor of Tenant and is properly exercised by Tenant, then Landlord shall reimburse Tenant for all of Tenant’s out-of-pocket fees and costs incurred prior to the date of such termination for design, space planning, architectural, engineering and construction management services in connection with this Lease and the Workletter, which reimbursement shall be paid by Landlord to Tenant within thirty (30) days after Landlord’s receipt of Tenant’s written request for such reimbursement, accompanied by copies of such invoices and other supporting documentation as Landlord may reasonably request to evidence the nature and amount of the fees and costs for which such reimbursement is requested.

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2.4 Acknowledgment Of Rent Commencement Dates. Promptly following the respective Rent Commencement Date for each Building or portion thereof, Landlord and Tenant shall execute a written acknowledgment of such Rent Commencement Date, the square footage of the Building or portion thereof (in the case of the Phase II Rent Commencement Dates) as to which the Rent Commencement Date applies, the Termination Date (if then determined) and related matters, substantially in the form attached hereto as Exhibit E (with appropriate insertions), which acknowledgment shall be deemed to be incorporated herein by this reference. Notwithstanding the foregoing requirement, the failure of either party to execute such a written acknowledgment shall not affect the determination of the applicable Rent Commencement Date, the applicable minimum rental and Operating Expense obligations, the Termination Date and related matters in accordance with the provisions of this Lease.

2.5 Holding Over. If Tenant holds possession of the Property or any portion thereof after the term of this Lease with Landlord’s written consent, then except as otherwise specified in such consent, Tenant shall become a tenant from month to month at [REDACTED] and otherwise upon the terms herein specified for the period immediately prior to such holding over and shall continue in such status until the tenancy is terminated by either party upon not less than thirty (30) days prior written notice. If Tenant holds possession of the Property or any portion thereof after the term of this Lease without Landlord’s written consent, then Landlord in its sole discretion may elect (by written notice to Tenant) to have Tenant became a tenant either from month to month or at will, at [REDACTED] and otherwise up [REDACTED] over, or may elect to pursue any and all legal remedies available to Landlord under applicable law with respect to such unconsented holding over by Tenant. Tenant shall indemnify and hold Landlord harmless from any loss, damage, claim, liability, cost or expense (including reasonable attorneys’ fees) resulting from any delay by Tenant in surrendering the Property (except with Landlord’s prior written consent), including but not limited to any claims made by a succeeding tenant by reason of such delay. Acceptance of rent by Landlord following expiration or termination of this Lease shall not constitute a renewal of this Lease.

[REDACTED]

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3. RENTAL

3.1 Minimum Rental.

(a) Rental Amounts. Tenant shall pay to Landlord as minimum rental for the respective Buildings or applicable portions thereof, in advance, without deduction, offset (except as specifically authorized under Paragraph 4(c) of the Workletter, if applicable), notice or demand, on or before the applicable Rent Commencement Date for the respective Building and on or before the First day of each subsequent calendar month of the initial term of this Lease, the following amounts per month (the “Minimum Rental”), subject to adjustment in accordance with the terms of this Section 3.1:

(i) For the Phase IA Building, beginning on the Phase I Rent, Commencement Date, an amount equal to the applicable amount per square foot from the following table multiplied by the square footage of the Phase IA Building as determined pursuant to Section 3.1(d):

[REDACTED]

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(ii) For the Phase IB Building, beginning on the Phase I Rent Commencement Date, an amount equal to the applicable amount per square foot from the following table multiplied by the square footage of the Phase IB Building as determined pursuant to Section 3.1(d):

[REDACTED]

(iii) For the Phase II Building, beginning on the Phase IIA Rent Commencement Date (with each successive phase of Tenant’s occupancy of the Phase II Building being brought under the following table as of the applicable Rent Commencement Date for such phase at the rental rate determined under the following table by counting from the Phase IIA Rent Commencement Date), an amount equal to the applicable amount per square foot from the following table multiplied by the aggregate square footage of all then applicable phases of the Phase II Building as determined pursuant to Section 3.1 (d):

[REDACTED]

(iv) If the obligation to pay Minimum Rental or additional rent hereunder commences on other than the first day of a calendar month or if the term of this Lease terminates on other than the last day of a calendar month, the Minimum Rental and any additional rent for such first or last month of the term of this Lease, as the case may be, shall be prorated based on the number of days the term of this Lease is in effect during such month. If an increase in Minimum Rental or additional rent becomes effective on a day other than the first day of a calendar month, the Minimum Rental or additional rent, as applicable, for that month shall be the sum of the two applicable rates, each prorated for the portion of the month during which such rate is in effect.

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(b) Rental Amounts During First Extended Term. If Tenant properly exercises its right to extend the term of this Lease pursuant to Section 2.6 hereof, the Minimum Rental for each Building as to which Tenant has elected to extend during the first year of the first extended term shall be equal to the initial fair market rental (as defined below) for the applicable Building, determined as of the commencement of such extended term in accordance with this Section 3.1(b), and as of the beginning of each subsequent year of the first extended term such Minimum Rental shall be increased by an amount equal to the greater of (i) three percent (3%) of the Minimum Rental in effect during the immediately preceding lease year or (ii) the fair market rental escalation percentage (as defined below) for the applicable Building, determined as of the commencement of such extended term in accordance with this Section 3.1(b). Upon Landlord’s receipt of a timely notice of Tenant’s exercise of its option to extend the term of this Lease, the parties shall have sixty (60) days in which to agree on the initial fair market rental and the applicable rental escalation percentage for the Buildings as of the commencement of the first extended term for the uses permitted hereunder. If the parties agree on such initial fair market rental and rental escalation percentage, they shall execute an amendment to this Lease stating the amount of the Minimum Rental during the first year of the extended term (determined in accordance with this Section 3.1(b)) and the annually increased Minimum Rental for the balance of the first extended term. If the parties are unable to agree on such initial fair market rental and/or applicable rental escalation percentage within such sixty (60) day period, then within fifteen (15) days after the expiration of such period each party, at its cost and by giving notice to the other party, shall appoint a real estate appraiser who is a member of the American Institute of Real Estate Appraisers, or any other similar organization, and has at least five (5) years experience appraising similar commercial properties in northeastern San Mateo County, to determine the initial fair market rental and applicable rental escalation percentage for the Buildings as of the commencement of the first extended term in accordance with the provisions of this Section 3.1(b). If either party fails to appoint an appraiser within the allotted time, the single appraiser appointed by the other party shall be the sole appraiser, If an appraiser is appointed by each party and the two appraisers so appointed are unable to agree upon the initial fair market rental and/or the applicable rental escalation percentage within thirty (30) days after the appointment of the second, the two appraisers shall appoint a third similarly qualified appraiser within ten (10) days after expiration of such 30-day period; if they are unable to agree upon a third appraiser, then either party may, upon not less than five (5) days notice to the other party, apply to the Presiding Judge of the San Mateo County Superior Court for the appointment of a third similarly qualified appraiser. Each party shall bear its own legal fees in connection with appointment of the third appraiser and shall bear one-half of any other costs of appointment of the third appraiser and of such third appraiser’s fee. The third appraiser, however selected, shall be a person who has not previously acted for either party in any capacity. Within thirty (30) days after the appointment of the third appraiser, a majority of the three appraisers shall set the initial fair market rental and the applicable rental escalation percentage for the first extended term and shall so notify the parties. If a majority are unable to agree within the allotted time, (i) the three appraised initial fair market rentals shall be added together and divided by three and the resulting quotient shall be the initial fair market rental for the first extended term, and (ii) the three appraised fair market rental escalation percentages shall be added together and divided by three and the resulting quotient shall be the fair market rental escalation percentage used in determining the applicable rental escalation percentage for purposes of clause (ii) of the first sentence of this Section 3.1(b), which determinations shall be binding on the parties and shall be enforceable in any further proceedings relating to this Lease. For purposes of this Section 3.1(b), the “fair market rental” and “fair market rental escalation percentage” for the respective Buildings shall be determined as follows: (x) in the case of a renewal term for any of the Buildings, with reference to the then prevailing market rental rates for properties in northeastern San Mateo County with shell and standard office, research and development improvements and site (common area) improvements comparable to those then existing in the applicable Building and on the Property, provided that no equipment or laboratory improvements shall be taken into account in determining such fair market rental; and (y) in the case of a lease or renewal term for any other building leased by Tenant under terms based on the terms of this Lease (for example, any building leased by Tenant pursuant to any of the provisions of Article 6 hereof, except to the extent any different basis of determination is specified in Landlord’s First Refusal Notice or First Offer Notice, if applicable, under such Article 6), with reference to the then prevailing market rental rates and then prevailing market rental escalation provisions for leases of comparable length of properties in the South San Francisco market with shell and office, research and development improvements and site (common area) improvements comparable to those then existing in the applicable building and on the Property, taking into account for such determination all tenant improvements then existing in the applicable building (including, but not limited to, equipment and laboratory improvements installed as part of the initial construction of tenant improvements in such building).

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(c) Rental Amounts During Second Extended Term. If Tenant properly exercises its right to a second extended term of this Lease pursuant to Section 2.6 hereof, the Minimum Rental during such second extended term shall be determined in the same manner provided in the preceding paragraph for the first extended term (initial fair market rental followed by subsequent annual escalations equal to the greater of 3% or fair market rental escalation percentage during the balance of the term), except that the determination shall be made as of the commencement of the second extended term.

(d) Determination of Square Footage for Rent Calculation Purposes. After completion of the Building Shell of each respective Building, Landlord shall cause the square footage of the respective Building (including, in the case of the Phase IB Building, the Connector Bridge if constructed as contemplated in Section 1.1(a) hereof) to be measured by Landlord’s architect, and at the commencement of each phase of Tenant’s occupancy of the Phase II Building, Landlord shall cause the square footage of the space actually used or occupied by Tenant in the Phase II Building to be measured by Landlord’s architect, in each case in accordance with the measurement formula specified in Section 1.1(d) of this Lease, which measurements by Landlord’s architect shall be subject to approval (not unreasonably withheld or delayed) by Tenant’s architect. Upon mutual approval of such measurement by Landlord’s and Tenant’s respective architects, the applicable square footages shall be set forth in the applicable Acknowledgment of Rent Commencement Date under Section 2.4 hereof and shall be used for calculation of Minimum Rental under Section 3.1(a), additional rent under Section 3.1(e) and Tenant’s Operating Cost Share under Section 9.1 for all applicable periods.

(e) Additional Rent for Tenant Improvement Costs. In consideration of Landlord’s willingness to provide the Tenant Improvement Allowance to Tenant in accordance with the provisions of the Workletter, Tenant agrees to pay to Landlord as additional rent hereunder, which additional rent shall be due with respect to each Building or phase thereof on the same dates and in the same manner as Minimum Rental for such Building or phase thereof, beginning on the applicable Rent Commencement Date for the applicable Building or phase thereof, an amount calculated separately for each such Building or phase thereof as follows: (i) for each of the Phase I Buildings, for the first one hundred twenty (120) months after the applicable Rent Commencement Date for the applicable Building, an amount equal to [REDACTED] per square foot per month multiplied by the applicable square footage for such Building as determined for purposes of Section 3.1(d) above, (ii) for each of the Phase I Buildings, for months one hundred twenty-one (121) through one hundred eighty (180) after the applicable Rent Commencement Date for the applicable Building, an amount equal to [REDACTED] per square foot per month multiplied by the applicable square footage for such Building as determined for purposes of Section 3.1(d) above, and (iii) for each phase of the Phase II Building, for the first one hundred eighty (180) months after the applicable Rent Commencement Date for such phase, an amount equal to [REDACTED] per square foot per month multiplied by the applicable square footage for such phase as determined for purposes of Section 3.1(d) above.

3.2 Late Charge. If Tenant fails to pay when due rental or other amounts due Landlord hereunder, such unpaid amounts shall bear interest for the benefit of Landlord at a rate equal to the lesser of fifteen percent (15%) per annum or the maximum rate permitted by law, from the date due to the date of payment. In addition to such interest, Tenant shall pay to Landlord a late charge in an amount equal to six percent (6%) of any installment of minimum rental and any other amounts due Landlord if not paid in full on or before the fifth (5th) day after such rental or other amount is due. Tenant acknowledges that late payment by Tenant to Landlord of rental or other amounts due hereunder will cause Landlord to incur costs not contemplated by this Lease, including, without limitation, processing and accounting charges and late charges which may be imposed on Landlord by the terms of any loan relating to the Property. Tenant further acknowledges that it is extremely difficult and impractical to fix the exact amount of such costs and that the late charge set forth in this Section 3.2 represents a fair and reasonable estimate thereof. Acceptance of any late charge by Landlord shall not constitute a waiver of Tenant’s default with respect to overdue rental or other amounts, nor shall such acceptance prevent Landlord from exercising any other rights and remedies available to it. Acceptance of rent or other payments by Landlord shall not constitute a waiver of late charges or interest accrued with respect to such rent or other payments or any prior installments thereof, nor of any other defaults by Tenant, whether monetary or non-monetary in nature, remaining uncured at the time of such acceptance of rent or other payments.

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4. [OMITTED]

5. CONSTRUCTION

5.1 Construction of Improvements.

(a) Landlord shall, at Landlord’s cost and expense (except as otherwise provided herein and in the Workletter), construct Landlord’s Work as defined in and in accordance with the terms and conditions of the Workletter. Landlord shall use its best efforts to complete such construction promptly, diligently and within the applicable time periods set forth in the estimated construction schedules attached hereto as Exhibit D and incorporated herein by this reference, as such schedules may be modified or revised from time to time in accordance with the Workletter, subject to Tenant Delays and Unavoidable Delays as defined in the Workletter.

(b) Tenant shall, at Tenant’s cost and expense (except as otherwise provided herein and in the Workletter), construct Tenant’s Work as defined in and in accordance with the terms and conditions of the Workletter.

5.2 Condition of Property. Landlord shall deliver the Building Shell for each Building and the other Improvements constructed by Landlord to Tenant clean and free of debris, promptly upon completion of construction thereof, and Landlord warrants to Tenant that each Building Shell and the other Improvements constructed by Landlord (i) shall be free from material structural defects and (ii) shall be constructed in compliance in all material respects with the plans and specifications developed pursuant to the Workletter and mutually approved (to the extent required thereunder) by Landlord and Tenant, subject to any changes implemented in such plans and specifications in accordance with the procedures set forth in the Workletter. If it is determined that this warranty has been violated in any respect, then it shall be the obligation of Landlord, after receipt of written notice from Tenant setting forth with specificity the nature of the violation, to correct promptly, at Landlord’s sole cost, the condition(s) constituting such violation. Tenant’s failure to give such written notice to Landlord within ninety (90) days after the Rent Commencement Date for the applicable Building shall give rise to a conclusive presumption that Landlord has complied with all Landlord’s obligations under this Section 5.2 with respect to the applicable Building, except with respect to latent defects (as to which such 90-day limit shall not apply). Without limiting the scope of Landlord’s obligations under the foregoing provisions of this Section 5.2, Landlord also agrees to either (x) use its best reasonable efforts to enforce when and as necessary, for the benefit of Tenant and the Improvements, any and all contractor’s and/or manufacturer’s warranties with respect to any of Landlord’s Work or, at Tenant’s request, (y) assign any or all of such warranties to Tenant for enforcement purposes (provided, however, that Landlord may reserve joint enforcement rights under such warranties to the extent of Landlord’s continuing obligations or warranties hereunder), and shall cooperate with Tenant in all reasonable respects in any enforcement of such assigned warranties. TENANT ACKNOWLEDGES THAT THE WARRANTIES CONTAINED IN THIS SECTION ARE IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, WITH RESPECT TO THE PHYSICAL CONDITION OF THE IMPROVEMENTS TO BE CONSTRUCTED BY LANDLORD AND THAT LANDLORD MAKES NO OTHER WARRANTIES EXCEPT AS EXPRESSLY SET FORTH IN THIS LEASE.

5.3 Compliance with Law. Landlord warrants to Tenant that the Building Shells and other Improvements constructed by Landlord (when constructed), as they exist on the respective applicable Rent Commencement Dates, but without regard to the use for which Tenant will occupy the Buildings, shall not violate any covenants or restrictions of record or any applicable law, building code, regulation or ordinance in effect on the applicable Rent Commencement Date. Tenant warrants to Landlord that the Tenant Improvements and any other improvements constructed by Tenant from time to time shall not violate any applicable law, building code, regulation or ordinance in effect on the applicable Rent Commencement Date or at the time such improvements are placed in service. If it is determined that any of these warranties has been violated, then it shall be the obligation of the warranting party, after written notice from the other

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party, to correct the condition(s) constituting such violation promptly, at the warranting party’s sole cost and expense. Tenant acknowledges that neither Landlord nor any agent of Landlord has made any representation or warranty as to the present or future suitability of the Property for the conduct of Tenant’s business or proposed business thereon.

[REDACTED]

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[REDACTED]

7. [OMITTED]

8. TAXES

8.1 Personal Property. Tenant shall be responsible for and shall pay prior to delinquency all taxes and assessments levied against or by reason of (a) any and all alterations, additions and items installed or placed on, in or about any of the Buildings by Tenant or for Tenant’s use and taxed as personal property rather than as real property, and/or (b) all personal property, trade fixtures and other property placed by Tenant on or about the Property. Upon request by Landlord, Tenant shall furnish Landlord with satisfactory evidence of Tenant’s payment thereof. If at any time during the term of this Lease any of said alterations, additions or personal property, whether or not belonging to Tenant, shall be taxed or assessed as part of the Property, then such tax or assessment shall be paid by Tenant to Landlord immediately upon presentation by Landlord of copies of the tax bills in which such taxes and assessments are included and shall, for the purposes of this Lease, be deemed to be personal property taxes or assessments under this Section 8.1.

8.2 Real Property. To the extent any real property taxes and assessments on any of the Buildings (including, but not limited to, the Improvements) are assessed directly to Tenant, Tenant shall be responsible for and shall pay prior to delinquency all such taxes and assessments levied against the Buildings. Upon request by Landlord, Tenant shall furnish Landlord with satisfactory evidence of Tenant’s payment thereof. To the extent the Buildings, the Property and/or the Improvements are taxed or assessed to Landlord following the applicable Rent Commencement Dates, such real property taxes and assessments shall constitute Operating Expenses (as that term is defined in Section 9.2 of this Lease) and shall be paid in accordance with the provisions of Article 9 of this Lease.

9. OPERATING EXPENSES

9.1 Liability For Operating Expenses.

(a) Tenant shall pay to Landlord, at the time and in the manner hereinafter set forth, as additional rental, Tenant’s Operating Cost Share (as hereinafter defined) of the Operating Expenses defined in Section 9.2, subject to adjustment pursuant to Sections 9.1(b) and (c) when applicable. The parties presently anticipate that the percentage amount constituting Tenant’s applicable share of Operating Expenses (“Tenant’s Operating Cost Share”), except as otherwise provided herein, will be [REDACTED] as of the Phase I Rent Commencement Date, [REDACTED] as of the Phase IIA Rent Commencement Date, [REDACTED] as of the Phase IIB Rent as of Commencement Date [REDACTED] of the Phase IIC Rent Commencement Date and [REDACTED] of the Phase IID Rent Commencement Date. Notwithstanding the foregoing and the provisions of Section 9.1(c), with respect to liability insurance premiums (except to the extent separately and specifically allocable to a Building, in which event Tenant’s Operating Cost Share with respect thereto shall be [REDACTED] for the Phase IA Building and [REDACTED] the Phase IB Building and [REDACTED] for the Phase II Building), the land component of real property taxes and assessments, common area lighting and maintenance expenses, and other similar expenses that are incurred or measured on a Center-wide basis (rather than’ being clearly and reasonably allocable or attributable to a specific Building alone, in which event Tenant’s Operating Cost Share with respect thereto shall be [REDACTED] for the Phase IA Building and the

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Phase IB Building and [REDACTED] for the Phase II Building) or that are incurred with respect to common area facilities, notwithstanding any other provisions of this Article 9, Tenant’s Operating Cost Share with respect to such Center-wide and/or common area expenses from and after each respective Rent Commencement Date, regardless of the status of construction and occupancy of the other contemplated buildings in the Center, shall be equal to the percentage amount which is equivalent to a fraction, the numerator of which is the actual square footage of the Building(s) as to which a Rent Commencement Date has then occurred, as determined on the basis of measurement set forth in Section 1.1(c) hereof, and the denominator of which is the sum of the actual square footage of all then completed buildings in the Center plus the proposed square footage (as reflected in Landlord’s entitlements for the Property) of all not yet completed buildings that Landlord proposes to construct in the Center (excluding the proposed child care facility and proposed stand-alone restaurant as hereinafter set forth), in each case as determined on the basis of measurement set forth in Section 1.1(c) hereof, consistently applied; provided, however, that the adjusted Tenant’s Operating Cost Share determined pursuant to this sentence shall be further adjusted from time to time to reflect (x) any difference between the actual square footage of any additional buildings completed in the Center from time to time and the proposed square footage at which such additional buildings were previously included in the application of the foregoing formula, and (y) any increase or decrease in the aggregate square footage of the buildings that Landlord proposes to construct in the Center as part of the initial phased development of the Center (such as, but not limited to, any decision by Landlord to defer indefinitely, beyond the normal and reasonable phasing of the Center, the construction of any of the planned buildings in the Center and/or any action by governmental authorities to reduce the aggregate square footage of the buildings that Landlord is entitled to construct in the Center pursuant to Landlord’s entitlements as amended from time to time), provided that in no event shall Tenant’s Operating Share be calculated with a denominator of less than [REDACTED] (except that such minimum denominator shall be reduced to the extent any square footage of existing or proposed buildings in the Center from time to time is removed from commercial use entirely, other than on a temporary or interim basis, as a result of casualty or condemnation, or to the extent any buildings in the Center from time to time cease to be operated and accounted for on an integrated basis with the rest of the Center for Operating Expense purposes as a result of the sale of a portion of the Property or otherwise).

(b) Tenant’s Operating Cost Share as specified in Section 9.1(a) as of the Phase I Rent Commencement Date is based upon an estimated area of [REDACTED] square feet for the Phase IA Building, an estimated area of [REDACTED] square feet for the Phase IB Building (not including the Connector Bridge contemplated in Section 1.1(a), but if such Connector Bridge is in fact constructed, the square footage thereof shall be included in the square footage of the Phase IB Building for purposes of alt calculations of Tenant’s Operating Cost Share under this Article 9) and an aggregate estimated area of [REDACTED] square feet for all of the buildings that Landlord presently expects to have in fully constructed and occupied condition on the Property at the Phase I Rent Commencement Date; Tenant’s Operating Cost Share as specified in Section 9.1(a) as of the Phase IIA Rent Commencement Date is based upon an estimated area of [REDACTED] square feet for Phase IIA and upon an aggregate estimated area [REDACTED] square feet for all of the buildings that Landlord presently expects to have in fully constructed and occupied condition on the Property at the Phase IIA Rent Commencement Date; Tenant’s Operating Cost Share as specified in Section 9.1(a) as of the Phase IIB Rent Commencement Date is based upon an estimated area of [REDACTED] square feet for Phase IIB and upon an aggregate estimated area of [REDACTED] square feet for all of the buildings that Landlord presently expects to have in fully constructed and occupied condition on the Property at the Phase IIB Rent Commencement Date; Tenant’s Operating Cost Share as specified in Section 9.1(a) as of the Phase IIC Rent Commencement Date is based upon an estimated area of [REDACTED] square feet for Phase IIC and upon an aggregate estimated area of [REDACTED] square feet for all of the buildings that Landlord presently expects to have in fully constructed and occupied condition on the Property at the Phase IIC Rent Commencement Date; and Tenant’s Operating Cost Share as specified in Section 9.1(a) as of the Phase IID Rent Commencement Date is based upon an estimated area of [REDACTED] Square feet for Phase IID and upon an aggregate estimated area of [REDACTED] square feet for all of the buildings that Landlord presently expects to have in fully constructed and occupied condition on the Property at the Phase IID Rent Commencement Date. If the actual area of the respective Buildings (when completed) or phases thereof (in the case of the Phase II Building) or of the other buildings existing from time to time in the Center, as determined on the basis of measurement set forth in Section 1.1(c) hereof (which basis of measurement shall be applied consistently for all buildings in the Center), differs from the assumed numbers set forth above

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(including, but not limited to, any such difference arising from the completion and occupancy of buildings in the Center before or after the respective Rent Commencement Dates hereunder, as contemplated in Section 9.1(c) below, and/or from the construction of the Connector Bridge contemplated in Section 1.1(a), if applicable), then Tenant’s Operating Cost Share shall be adjusted to reflect the actual areas so determined as they exist from time to time. In no event, however, shall the square footage of any child care facility or stand-alone restaurant on the Property be included as part of the square footage of buildings on the Property in calculating Tenant’s Operating Cost Share, nor shall any costs or expenses relating to the proposed child care facility and proposed stand-alone restaurant on the Property be included in Operating Expenses as hereinafter defined. In the case of expenses that are incurred or measured on a Center-wide basis or that are incurred with respect to Common Area facilities, Landlord shall allocate a reasonable share of such expenses to the proposed child care facility and proposed stand-alone restaurant on the Property and shall exclude such share from Operating Expenses pursuant to the preceding sentence.

(c) As Landlord constructs additional buildings in the Center (other than those described in the first sentence of Section 9.1(b) as already being taken into account in the estimated figures set forth above), Tenant’s Operating Cost Share shall be adjusted from time to time to be equal to the percentage determined by dividing the gross square footage of the Building(s) as to which a Rent Commencement Date has occurred hereunder, as they then exist, by the gross square footage of all buildings located in the Center (subject to the exclusion set forth in Section 9.1(b) with respect to the proposed child care facility and proposed restaurant). In determining such percentage, a building shall be taken into account from and after the date on which a tenant first enters into possession of the building or a portion thereof; the determination of the gross square footage of any such building by Landlord’s architect in a manner consistent with the manner in which other buildings in the Center are measured shall be final and binding upon the parties; and costs and expenses relating to a new building shall be taken into account as Operating Expenses under this Article 9 only from and after the date on which the square footage of the building is taken into account in determining Tenant’s Operating Cost Share under the criteria set forth in this paragraph.

9.2 Definition Of Operating Expenses.

(a) Subject to the exclusions and provisions set forth in this Article 9, the term “Operating Expenses” shall mean the total costs and expenses incurred by or allocable to Landlord for management, operation and maintenance of the Improvements, the Property and the Center, including, without limitation, costs and expenses of (i) insurance (including, but not limited to, earthquake insurance and environmental insurance), property management (provided that Tenant’s allocable share of property management fees for any applicable period during the term of this Lease shall not exceed a maximum amount equal to one and one half percent (1.5%) of the Minimum Rental payable hereunder with respect to such period), landscaping, and the operation, repair and maintenance of buildings and Common Areas; (ii) all utilities and services; (iii) real and personal property taxes and assessments or substitutes therefor levied or assessed against the Center or any part thereof, including (but not limited to) any possessory interest, use, business, license or other taxes or fees, any taxes imposed directly on rents or services, any assessments or charges for police or fire protection, housing, transit, open space, street or sidewalk construction or maintenance or other similar services from time to time by any governmental or quasi-governmental entity, and any other new taxes on landlords in addition to taxes now in effect; (iv) supplies, equipment, utilities and tools used in management, operation and maintenance of the Center; (v) capital improvements to the Property, the Improvements or the Center, amortized over their useful lives as determined by Landlord’s accountants consistent with generally accepted accounting principles and/or tax accounting principles, (aa) which reduce or will cause future reduction of other items of Operating Expenses for which Tenant is otherwise required to contribute or (bb) which are required by law, ordinance, regulation or order of any governmental authority; and (vi) any other costs (including, but not limited to, any parking or utilities fees or surcharges not otherwise specifically addressed elsewhere in this Lease) allocable to or paid by Landlord, as owner of the Center or Improvements, pursuant to any applicable laws, ordinances, regulations or orders of any governmental or quasi-governmental authority or pursuant to the terms of any declarations of covenants, conditions and restrictions now or hereafter affecting the Center or any other property over which Tenant has non-exclusive usage rights as contemplated in Section 1.1(b) hereof. Operating Expenses shall not include any costs attributable to the work for which Landlord is required to pay under Article 5 or the Workletter, nor any costs attributable to the initial construction of buildings or

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Common Area improvements in the Center, nor any costs attributable to buildings the square footage of which is not taken into account in determining Tenant’s Operating Cost Share under Section 9.1 for the applicable period. The distinction between items of ordinary operating maintenance and repair and items of a capital nature shall be made in accordance with generally accepted accounting principles applied on a consistent basis or in accordance with tax accounting principles, as determined in good faith by Landlord’s accountants.

(b) Notwithstanding any other provisions of this Section 9.2, the following shall not be included within Operating Expenses: (i) rent paid to any ground lessor; (ii) the cost of constructing tenant improvements for any other tenant of a Building or the Center; (iii) the costs of special services, goods or materials provided to any other tenant of a Building or the Center and not offered or made available to Tenant; (iv) repairs covered by proceeds of insurance or from funds provided by Tenant or any other tenant of the Center, or as to which any, other tenant of the Center is obligated to make such repairs or to pay the cost thereof; (v) legal fees, advertising costs, commissions or other related expenses incurred by Landlord in connection with the leasing of space to individual tenants of the Center; (vi) repairs, alterations, additions, improvements or replacements needed to rectify or correct any defects in the original design, materials or workmanship of a Building, the Center or the Common Areas; (vii) damage and repairs necessitated by the negligence or willful misconduct of Landlord or of Landlord’s employees, contractors or agents; (viii) Landlord’s general overhead expenses not related to the Buildings or the Center; (ix) legal fees, accountants’ fees and other expenses incurred in connection with disputes with tenants or other occupants of the Center, or in connection with the enforcement of the terms of any leases with tenants or the defense of Landlord’s title to or interest in the Center or any part thereof; (x) costs incurred due to a violation by Landlord or any other tenant of the Center of the terms and conditions of any lease; (xi) costs of any service provided to Tenant or to other occupants of a Building or the Center for which Landlord is reimbursed other than through recovery of Operating Expenses; (xii) personal property taxes due and payable by any other tenant of the Center; (xiii) costs incurred by Landlord pursuant to Article 17 of this Lease in connection with an event of casualty or condemnation; (xiv) depreciation on buildings; (xv) interest; (xvi) capital items (other than as expressly provided above); (xvii) payments on debt (principal or interest); (xviii) legal fees; (xix) amounts paid to any affiliates of Landlord (i.e., persons or companies controlling, controlled by or under common control with Landlord) for provision of services, except to the extent that the costs of such services do not exceed a reasonable and competitive rate for such services in the market for provision of comparable commercial services in the San Francisco Bay Area; (xx) any bad debt losses, rent losses or reserves for bad debt; (xxi) any costs relating to the creation, maintenance and operation of and the internal accounting for the legal entity which constitutes the landlord hereunder; and (xxii) any late fees or penalties or similar fees resulting from delinquent payment by Landlord of any taxes, fees or contract amounts. Moreover, Operating Expenses shall not include any expenses of operation and maintenance of the parking structure and parking areas on the Property or of measures undertaken by Landlord pursuant to the TDMP (as defined in Section 21.20(a)), except to the extent such expenses in the aggregate exceed, for the applicable period, aggregate parking revenues received by Landlord with respect to that period from tenants under provisions comparable to Section 21.20(b) hereof and from any other users paying hourly, daily, monthly or other fees for the use of such parking structure and/or parking areas from time to time. Landlord presently estimates that parking-related revenues will generally exceed expenses of operation and maintenance of the parking structure and parking areas on the Property, leaving a portion of such revenues available to support TDMP measures undertaken by Landlord as contemplated in the preceding sentence.

9.3 Determination and Payment of Operating Expenses. On or before the Phase I Rent Commencement Date and during the last month of each calendar year of the term of this Lease (“Lease Year”), or as soon thereafter as practical, Landlord shall provide Tenant notice of Landlord’s estimate of the Operating Expenses for the ensuing Lease Year or applicable portion thereof. On or before the first day of each month during the ensuing Lease Year or applicable portion thereof, beginning on the Phase I Rent Commencement Date, Tenant shall pay to Landlord Tenant’s Operating Cost Share of the portion of such estimated Operating Expenses allocable (on a prorata basis) to such month; provided, however, that if such notice is not given in the last month of a Lease Year, Tenant shall continue to pay on the basis of the prior year’s estimate, if any, until the month after such notice is given. If at any time or times it appears to Landlord that the actual Operating Expenses will vary from Landlord’s estimate by more than five percent (5%), Landlord may, by notice to Tenant, revise its estimate for such year and

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subsequent payments by Tenant for such year shall be based upon such revised estimate. In the event of any subsequent rebate, refund, adjustment or surcharge with respect to any item of Operating Expenses allocable to any portion of the term of this Lease, the amount of such rebate, refund, adjustment or surcharge shall be for Tenant’s benefit or account.

9.4 Final Accounting For Lease Year.

(a) Within ninety (90) days after the close of each Lease Year, or as soon after such 90-day period as practicable, Landlord shall deliver to Tenant a statement of Tenant’s Operating Cost Share of the Operating Expenses for such Lease Year prepared by Landlord from Landlord’s books and records, which statement shall be final and binding on Landlord and Tenant (except as provided in Section 9.4(b)). If on the basis of such statement Tenant owes an amount that is more or less than the estimated payments for such Lease Year previously made by Tenant, Tenant or Landlord, as the case may be, shall pay the deficiency to the other party within thirty (30) days after delivery of the statement. Failure or inability of Landlord to deliver the annual statement within such ninety (90) day period shall not impair or constitute a waiver of Tenant’s obligation to pay Operating Expenses, or cause Landlord to incur any liability for damages.

(b) At any time within four (4) months after receipt of Landlord’s annual statement of Operating Expenses as contemplated in Section 9.4(a), Tenant shall be entitled, upon reasonable written notice to Landlord and during normal business hours at Landlord’s office or such other places as Landlord shall designate, to inspect and examine those books and records of Landlord relating to the determination and payment of Operating Expenses relating to the immediately preceding Lease Year covered by such annual, statement or, if Tenant so elects by written notice to Landlord, to request an independent audit of such books and records. The independent audit of the books and records shall be conducted by a certified public accountant reasonably acceptable to both Landlord and Tenant or, if the parties are unable to agree, by a certified public accountant appointed by the Presiding Judge of the San Mateo County Superior Court upon the application of either Landlord or Tenant (with notice to the other party). In either event, such certified public accountant shall be one who is not then employed in any capacity by Landlord or Tenant or by any of their respective affiliates. The audit shall be limited to the determination of the amount of Operating Expenses for the subject Lease Year, and shall be based on generally accepted accounting principles and tax accounting principles, consistently applied. If it is determined, by mutual agreement of Landlord and Tenant or by independent audit, that the amount of Operating Expenses billed to or paid by Tenant for the applicable Lease Year was incorrect, then the appropriate party shall pay to the other party the deficiency or overpayment, as applicable, within thirty (30) days after the final determination of such deficiency or overpayment. All costs and expenses of the audit shall be paid by Tenant unless the audit shows that Landlord overstated Operating Expenses for the subject Lease Year by more than five percent (5%), in which case Landlord shall pay all costs and expenses of the audit. Each party agrees to maintain the confidentiality of the findings of any audit in accordance with the provisions of this Section 9.4.

9.5 Proration. If a Rent Commencement Date falls on a day other than the first day of a Lease Year or if this Lease terminates on a day other than the last day of a Lease Year, then the amount of Operating Expenses payable by Tenant with respect to such first or last partial Lease Year shall be prorated on the basis which the number of days during such Lease Year in which this Lease is in effect bears to 365. The termination of this Lease shall not affect the obligations of Landlord and Tenant pursuant to Section 9.4 to be performed after such termination.

10. UTILITIES

10.1 Payment. Commencing with the applicable Rent Commencement Date for each Building and thereafter throughout the term of this Lease, Tenant shall pay, before delinquency, all charges for water, gas, heat, light, electricity, power, sewer, telephone, alarm system, janitorial and other services or utilities supplied to or consumed in or with respect to such Building (other than any separately metered costs for water, electricity or other services or utilities furnished with respect to the Common Areas, which costs shall be paid by Landlord and shall constitute Operating Expenses under Section 9.2 hereof), including any taxes on such services and utilities. It is the intention of the parties that all such services and utilities shall be separately metered to each Building and, in the case of the Phase II Building, to Tenant’s

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premises in such Building. In the event that any of such services or utilities supplied to any Building are not separately metered (or, in the case of the Phase II Building, are not separately metered to Tenant’s premises in that Building), then the amount thereof shall be an item of Operating Expenses allocable to the specific Building and shall be allocated to and paid by the tenants of that specific Building as provided in Article 9.

10.2 Interruption. There shall be no abatement of rent or other charges required to be paid hereunder and Landlord shall not be liable in damages or otherwise for interruption or failure of any service or utility furnished to or used with respect to any Building or the Property because of accident, making of repairs, alterations or improvements, severe weather, difficulty or inability in obtaining services or supplies, labor difficulties or any other cause unless the interruption or failure of a service or utility is caused by the negligence or willful misconduct of Landlord, its agents, employees or contractors, in which case all rent hereunder shall be abated for each Building for each day that such service or utility is not available at such Building as a result of such negligence or willful misconduct, beginning on the first business day following the day on which the unavailability of such service or utility at the applicable Building commences, and Landlord shall be liable for Tenant’s actual damages (but not lost profits or other consequential damages) as a result of the unavailability of such service or utility caused by such negligence or willful misconduct. Notwithstanding the foregoing Landlord agrees that except in case of emergency, it will not voluntarily interrupt, shut down, or otherwise interfere with utilities or services to any Building between the hours of 8:00 a.m. and 5:00 p.m. (excluding weekends and holidays) for any reason, including without limitation, development of other buildings and improvements on the Property (but excluding any necessary interruption or shutdown of utilities or services in connection with the construction of any of the Buildings themselves). In the event Landlord violates the foregoing prohibition, all rent hereunder for each Building shall be abated for each day any service or utility is not available at such Building as a result of Landlord’s voluntary interruption, shutdown or interference therewith and Tenant shall have the right to exercise all rights and remedies available at law or in equity for such violation, including the right to enjoin Landlord’s actions which are the cause of such interruption, shut down or interference. In the event of any interruption or shutdown of utilities or services by Landlord under emergency circumstances, Landlord shall use reasonable efforts to provide Tenant with oral notice of such interruption or shutdown as promptly as the circumstances reasonably permit.

11. ALTERATIONS; SIGNS

11.1 Right To Make Alterations. Tenant shall make no alterations, additions or improvements to the Property without the prior written consent of Landlord, which consent shall not be unreasonably withheld or delayed, except that Tenant shall not be required to obtain such consent for interior non-structural alterations costing less than Fifty Thousand Dollars ($50,000.00) for any single project (i.e., any single item of alterations or set of related alterations in a Building) and less than One Hundred Thousand Dollars ($100,000.00) in the aggregate with respect to the applicable Building, on a Building by Building basis, during any twelve (12) month period. All such alterations, additions and improvements shall be completed with due diligence in a first-class workmanlike manner, in compliance with plans and specifications approved in writing by Landlord and in compliance with all applicable laws, ordinances, rules and regulations, and to the extent Landlord’s consent is not otherwise required hereunder for such alterations, additions or improvements, Tenant shall give prompt written notice thereof to Landlord. Tenant shall cause any contractors engaged by Tenant for work on the Property to maintain public liability and property damage insurance, and other customary insurance, with such terms and in such amounts as Landlord may reasonably require, naming as additional insureds Landlord and any of its members, partners, shareholders, property managers, lenders, agents and employees designated by Landlord for this purpose, and shall furnish Landlord with certificates of insurance or other evidence that such coverage is in effect. Notwithstanding any other provisions of this Section 11.1, under no circumstances shall Tenant make any structural alterations or improvements, or any substantial changes to the roof or substantial equipment installations on the roof, or any substantial changes or alterations to building systems, without Landlord’s prior written consent.

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11.2 Title To Alterations. All alterations, additions and improvements installed in, on or about the Buildings or the Property shall become part of the Improvements and the property of Landlord, unless Landlord elects to require Tenant to remove the same upon the termination of this Lease; provided, however, that the foregoing shall not apply to (i) any Tenant Improvements, (ii) any other alterations, additions or improvements or (iii) Tenant’s movable furniture, equipment and trade fixtures, to the extent Tenant can demonstrate that any such items described in the preceding clauses (i) through (iii) were acquired and installed by Tenant at Tenant’s sole expense, without any use of funds from the Tenant Improvement Allowance under the Workletter, and are not an integral part of the applicable Building’s structure, interior architectural improvements, HVAC, plumbing or electrical systems or other standard operating systems. All of such items described in clauses (i) through (iii) of the preceding sentence and meeting the requirements set forth following clause (iii) in the preceding sentence (in all events including, but not limited to, lab benches, fume hoods and portable cold rooms, to the extent they meet the requirements set forth following clause (iii) in the preceding sentence) may (and, if duly elected by Landlord hereunder, shall) be removed by Tenant upon termination of this Lease. Tenant shall promptly repair any damage caused by its removal of any such improvements from time to time. Notwithstanding any other provisions of this Article 11, however, under no circumstances shall Tenant have any right to remove from the Buildings or the Property, at the expiration or termination of this Lease, any lab benches, fume hoods, cold rooms or other similar improvements and equipment installed in the Buildings with use of funds from the Tenant Improvement Allowance. Tenant shall also be responsible, to the extent provided in Section 12.2(c) hereof, for the cost of removal of the Connector Bridge at the expiration or termination of this Lease if such Connector Bridge is constructed as contemplated in Section 1.1(a) hereof. Notwithstanding any other provisions of this Article 11, (x) it is the intention of the parties that Landlord shall be entitled to claim all tax attributes associated with alterations, additions, improvements and equipment constructed or installed by Tenant or Landlord with funds provided by Landlord pursuant to the Tenant Improvement Allowance; and (y) it is the intention of the parties that Tenant shall be entitled to claim, during the term of this Lease, all tax attributes associated with alterations, additions, improvements and equipment constructed or installed by Tenant with Tenant’s own funds (and without any payment or reimbursement by Landlord pursuant to the Tenant Improvement Allowance), despite the fact that many items described in this clause (y) may be characterized in this Section 11.2 as becoming Landlord’s property upon installation, in recognition of the fact that Tenant will have installed and paid for such items, will have the right of possession and use of such items during the term of this Lease and will have the obligation to pay (directly or indirectly) property taxes on such items, carry insurance on such items and bear the risk of loss with respect to such items under Article 17 hereof. If and to the extent it becomes necessary, in implementation of the foregoing intentions, to identify (either specifically or on a percentage basis, as may be required under applicable tax laws) which alterations, additions, improvements and equipment constructed as part of Tenant’s Work under the Workletter have been funded through the Tenant Improvement Allowance and which have been constructed or installed with Tenant’s own funds, Landlord and Tenant agree to cooperate reasonably and in good faith to make such an identification by mutual agreement.

11.3 Tenant Trade Fixtures. Notwithstanding the provisions of Sections 11.1 and 11.2, but subject to the third sentence of Section 11.2 and to Section 11.5 (which shall be controlling in the case of signs, logos and insignia), Tenant may install, remove and reinstall trade fixtures without Landlord’s prior written consent, except that installation and removal of any trade fixtures which are affixed to the Buildings or the Property or which affect the exterior or structural portions of the Buildings or the building systems shall require Landlord’s written approval. Tenant shall immediately repair any damage caused by installation and removal of trade fixtures under this Section 11.3.

11.4 No Liens. Tenant shall at all times keep the Buildings and the Property free from all liens and claims of any contractors, subcontractors, materialmen, suppliers or any other parties employed either directly or indirectly by Tenant in construction work on the Buildings or the Property. Tenant may contest any claim of lien, but only if, prior to such contest, Tenant either (i) posts security in the amount of the claim, plus estimated costs and interest, or (ii) records a bond of a responsible corporate surety in such amount as may be required to release the lien from the Buildings and the Property. Tenant shall indemnify, defend and hold Landlord harmless against any and all liability, loss, damage, cost and other expenses, including, without limitation, reasonable attorneys’ fees, arising out of claims of any lien for work performed or materials or supplies furnished at the request of Tenant or persons claiming under Tenant.

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11.5 Signs. Tenant shall have the right to display its corporate name, logo and/or insignia with lighted signage on the exterior of the Buildings and in front of the entrance to each Building, subject to (a) Landlord’s prior approval as to location, size, design and composition (which approval shall not be unreasonably withheld or delayed), (b) the sign criteria established for the Center from time to time and (c) all restrictions and requirements of applicable law and of any covenants, conditions and restrictions or other written agreements now or hereafter applicable to the Property. Tenant shall immediately repair any damage caused by installation and removal of signs under this Section 11.5 from time to time. In the event Landlord installs at the Project any monument sign(s) on which identification signage for any individual tenants is included, Tenant shall be entitled to have identification signage on such monument sign(s) on a basis comparable to that made available to any other tenants.

12. MAINTENANCE AND REPAIRS

12.1 Landlord’s Work.

(a) Landlord shall repair and maintain or cause to be repaired and maintained the Common Areas of the Center, the roofs (structural portions only), exterior walls and other structural portions of the Buildings, any demising walls between Tenant’s portion of the Phase II Building and the retail portion of the Phase II Building (other than painting, minor surface damage and other cosmetic matters affecting only Tenant’s side of any such demising walls), and any building systems that serve, in common, both Tenant’s portion of the Phase II Building and the retail portion of the Phase II Building. The cost of all work performed by Landlord under this Section 12.1 shall be an Operating Expense hereunder, except to the extent such work (i) is required due to the negligence of Landlord, (ii) is a capital expense not includible as an Operating Expense under Section 9.2 hereof, or (iii) is required due to the negligence or willful misconduct of Tenant or its agents, employees or invitees (in which event Tenant shall bear the full cost of such work pursuant to the indemnification provided in Section 14.6 hereof, subject to the release set forth in Section 14.4 hereof). Tenant knowingly and voluntarily waives the right to make repairs at Landlord’s expense, except to the extent expressly set forth in Section 12.1(b), or to offset the cost thereof against rent, under any law, statute, regulation or ordinance now or hereafter in effect.

(b) If Landlord fails to perform any repairs or maintenance required to be performed by Landlord on any of the Buildings under Section 12.1(a) and such failure continues for thirty (30) days or more after Tenant gives Landlord written notice of such failure (or, if such repairs or maintenance cannot reasonably be performed within such 30-day period, then if Landlord fails to commence performance within such 30-day period and thereafter to pursue such performance diligently to completion), then except as otherwise expressly excluded herein. Tenant shall have the right to perform such repairs or maintenance and Landlord shall reimburse Tenant for the reasonable cost thereof within fifteen (15) days after written notice from Tenant of the completion and cost of such work, accompanied by copies of invoices or other reasonable supporting documentation. Under no circumstances, however, shall Tenant have any right to offset the cost of any such work against rent or other charges falling due from time to time under this Lease. Moreover, under no circumstances shall this Section 12.1(b) authorize Tenant to perform any of Landlord’s repairs or maintenance obligations (x) in the Phase II Building, except to the extent the conditions requiring repair or maintenance affect only Tenant’s portion of the Phase II Building and not the retail portion of the Phase II Building, or (y) in the Common Areas of the Property.

12.2 Tenant’s Obligation For Maintenance.

(a) Good Order, Condition And Repair. Except as provided in Section 12.1 hereof, Tenant at its sole cost and expense shall keep and maintain in good and sanitary order, condition and repair the Buildings (from and after the applicable Rent Commencement Date for each Phase I Building and for each phase of the Phase II Building) and every part thereof, wherever located, including but not limited to the roofs (non-structural portions only), signs, interiors, ceilings, electrical systems, plumbing systems, telephone and communications systems of the Buildings, the HVAC equipment and related mechanical systems serving the Buildings (for which equipment and systems Tenant shall enter into a service contract with a person or entity designated or approved by Landlord), all doors, door checks, windows, plate glass, door fronts, exposed plumbing and sewage and other utility facilities, fixtures, lighting, wall surfaces, floor surfaces and ceiling surfaces of the Buildings and all other interior repairs, foreseen and

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unforeseen, with respect to the Buildings, as required; provided, however, that (x) Tenant’s ordinary repair obligation with respect to any demising walls between Tenant’s portion of the Phase II Building and the retail portion of the Phase II Building shall be limited to painting, minor surface damage and other cosmetic matters affecting only Tenant’s side of any such demising walls, and (y) Tenant’s ordinary repair obligation with respect to building systems in the Phase II Building shall be limited to building systems or portions thereof that serve only Tenant’s portion of the Phase II Building and shall not include building systems or portions thereof which serve, in common, both Tenant’s portion of the Phase II Building and the retail portion of the Phase II Building.

(b) Landlord’s Remedy. If Tenant, after notice from Landlord, fails to make or perform promptly any repairs or maintenance which are the obligation of Tenant hereunder, Landlord shall have the right, but shall not be required, to enter the applicable Building(s) and make the repairs or perform the maintenance necessary to restore the applicable Building(s) to good and sanitary order, condition and repair. Immediately on demand from Landlord, the cost of such repairs shall be due and payable by Tenant to Landlord.

(c) Condition Upon Surrender; Removal of Connector Bridge. At the expiration or sooner termination of this Lease, Tenant shall surrender the Buildings and the Improvements, including any additions, alterations and improvements thereto, broom clean, in good and sanitary order, condition and repair, ordinary wear and tear and casualty damages (the latter of which shall be governed by the provisions of Article 17 hereof) excepted, first, however, removing all goods and effects of Tenant and all and fixtures and items required or permitted to be removed pursuant to this Lease (including, but not limited to, any such removal required as a result of an election duly made by Landlord to require such removal as contemplated in Section 11.2), and repairing any damage caused by such removal. In addition, notwithstanding any other provisions of this Lease, if the Connector Bridge is constructed as contemplated in Section 1.1(a) hereof and if Landlord notifies Tenant in writing, prior to or within six (6) months after the expiration or sooner termination of this Lease, that Landlord wishes, in its sole discretion, to remove the Connector Bridge following the expiration or sooner termination of this Lease in order to facilitate the re-leasing of the Phase I Buildings, then Tenant shall be responsible for all costs reasonably incurred by Landlord in connection with the removal of the Connector Bridge and the restoration and repair of the areas where the Connector Bridge was attached to the respective Phase I Buildings, and Tenant shall reimburse the amount of such costs to Landlord from time to time within twenty (20) days after receipt of Landlord’s written request(s) for reimbursement, accompanied by supporting documentation evidencing, in reasonable detail, the costs for which such reimbursement is requested. Tenant expressly waives any and all interest in any personal property and trade fixtures not removed from the Property by Tenant at the expiration or termination of this Lease, agrees that any such personal property and trade fixtures may, at Landlord’s election, be deemed to have been abandoned by Tenant, and authorizes Landlord (at its election and without prejudice to any other remedies under this Lease or under applicable law) to remove and either retain, store or dispose of such property at Tenant’s cost and expense, and Tenant waives all claims against Landlord for any damages resulting from any such removal, storage, retention or disposal.

13. USE OF PROPERTY

13.1 Permitted Use. Subject to Sections 13.3 and 13.4 hereof, Tenant shall use the Buildings solely as laboratory and research and development facilities, including (but not limited to) wet chemistry and biology labs, clean rooms, storage and use of toxic and radioactive materials incidental to such laboratory, research and development activities (subject to the provisions of Section 13.6 hereof), storage and use of laboratory animals, administrative offices, and other lawful purposes related to or incidental to such research and development use (subject in each case to receipt of alt necessary approvals from the City of South San Francisco and other governmental agencies having jurisdiction over the Buildings), and for no other purpose without Landlord’s written consent (not to be unreasonably withheld or delayed).

13.2 [Omitted.]

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13.3 No Nuisance. Tenant shall not use the Buildings or the Property for or carry on or permit upon the Property or any part thereof any offensive, noisy or dangerous trade, business, manufacture, occupation, odor or fumes, or any nuisance or anything against public policy, nor interfere with the rights or business of Landlord in the Buildings or the Property, nor commit or allow to be committed any waste in, on or about the Property. Tenant shall not do or permit anything to be done in or about the Property, nor bring nor keep anything therein, which will in any way cause the Property to be uninsurable with respect to the insurance required by this Lease or with respect to standard fire and extended coverage insurance with vandalism, malicious mischief and riot endorsements.

13.4 Compliance With Laws.

(a) Tenant shall not use the Buildings or the Property, or permit the Buildings or the Property to be used, in whole or in part for any purpose or use that is in violation of any applicable laws, ordinances, regulations or rules of any governmental agency or public authority. Tenant shall keep the Buildings and the Improvements equipped with all safety appliances required by law, ordinance or insurance on the Property, or any order or regulation of any public authority, because of Tenant’s particular use of the Property. Tenant shall procure all licenses and permits required for Tenant’s use of the Property. Tenant shall use the Property in strict accordance with all applicable ordinances, rules, laws and regulations and shall comply with all requirements of all governmental authorities now in force or which may hereafter be in force pertaining to the use of the Property by Tenant, including, without limitation, regulations applicable to noise, water, soil and air pollution, and making such nonstructural alterations and additions thereto as may be required from time to time by such laws, ordinances, rules, regulations and requirements of governmental authorities or insurers of the Property (collectively, “Requirements”) because of Tenant’s construction of improvements or other particular use of the Property. Any structural alterations or additions required from time to time by applicable Requirements because of Tenant’s construction of improvements in the Buildings or other particular use of the Property shall, at Landlord’s election, either (i) be made by Tenant, at Tenant’s sole cost and expense, in accordance with the procedures and standards set forth in Section 11.1 for alterations by Tenant, or (ii) be made by Landlord at Tenant’s sole cost and expense, in which event Tenant shall pay to Landlord as additional rent, within ten (10) days after demand by Landlord, an amount equal to all reasonable costs incurred by Landlord in connection with such alterations or additions. The judgment of any court, or the admission by Tenant in any proceeding against Tenant, that Tenant has violated any law, statute, ordinance or governmental rule, regulation or requirement shall be conclusive of such violation as between Landlord and Tenant.

(b) In compliance with requirements imposed upon Landlord by an Owner Participation Agreement between Landlord and The Redevelopment Agency of the City of South San Francisco, Tenant hereby agrees to and accepts the following provision:

“Tenant herein covenants by and for itself and its successors and assigns, and all persons claiming under or through it, and this Lease is made and accepted upon and subject to the conditions that there shall be no discrimination against or segregation of any person or group of persons on account of race, color, religion, creed, sex, marital status, ancestry or national origin in the leasing, subleasing, transferring, use, occupancy, tenure or enjoyment of the property herein leased, nor shall Tenant or any person claiming under or through it establish or permit any such practice or practices of discrimination or segregation with reference to the selection, location, number, use or occupancy of tenants, lessees, sublessees, subtenants or vendees in the property herein leased.”

13.5 Liquidation Sales. Tenant shall not conduct or permit to be conducted any auction, bankruptcy sale, liquidation sale, or going out of business sale, in, upon or about the Property, whether said auction or sale be voluntary, involuntary or pursuant to any assignment for the benefit of creditors, or pursuant to any bankruptcy or other insolvency proceeding.

13.6 Environmental Matters.

(a) For purposes of this Section, “hazardous substance” shall mean the substances included within the definitions of the term “hazardous substance” under (i) the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended, 42 U.S.C. §§ 9601 et seq., and the regulations promulgated thereunder, as amended, (ii) the California Carpenter-Presley-Tanner Hazardous Substance Account Act, California Health & Safety Code §§ 25300 et seq., and regulations promulgated thereunder, as amended, (iii) the

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Hazardous Materials Release Response Plans and Inventory Act, California Heath & Safety Code §§ 25500 et seq., and regulations promulgated thereunder, as amended, and (iv) petroleum; “hazardous waste” shall mean (i) any waste listed as or meeting the identified characteristics of a “hazardous waste” under the Resource Conservation and Recovery Act of 1976, 42 U.S.C. §§ 6901 et seq., and regulations promulgated pursuant thereto, as amended (collectively, “RCRA”), (ii) any waste meeting the identified characteristics of “hazardous waste,” “extremely hazardous waste” or “restricted hazardous waste” under the California Hazardous Waste Control Law, California Health & Safety Code §§ 25100 et seq., and regulations promulgated pursuant thereto, as amended (collectively, the “CHWCL”), and/or (iii) any waste meeting the identified characteristics of “medical waste” under California Health & Safety Code §§ 25015-25027.8, and regulations promulgated thereunder, as amended; and “hazardous waste facility” shall mean a hazardous waste facility as defined under the CHWCL.

(b) Without limiting the generality of the obligations set forth in Section 13.4 of this Lease:

(i) Tenant shall not cause or permit any hazardous substance or hazardous waste to be brought upon, kept, stored or used in or about the Property without the prior written consent of Landlord, which consent shall not be unreasonably withheld or delayed, except that Tenant, in connection with its permitted use of the Property as provided in Section 13.1, may keep, store and use materials that constitute hazardous substances which are customary for such permitted use, provided such hazardous substances are kept, stored and used in quantities which are customary for such permitted use and are kept, stored and used in full compliance with clauses (ii) and (iii) immediately below.

(ii) Tenant shall comply with all applicable laws, rules, regulations, orders, permits, licenses and operating plans of any governmental authority with respect to the receipt, use, handling, generation, transportation, storage, treatment and/or disposal of hazardous substances or wastes by Tenant or its agents or employees, and Tenant shall provide Landlord with copies of all permits, licenses, registrations and other similar documents that authorize Tenant to conduct any such activities in connection with its authorized use of the Property from time to time.

(iii) Tenant shall not (A) operate on or about the Property any facility required to be permitted or licensed as a hazardous waste facility or for which interim status as such is required, nor (B) store any hazardous wastes on or about the Property for ninety (90) days or more, nor (C) conduct any other activities on or about the Property that could result in the Property being deemed to be a “hazardous waste facility” (including, but not limited to, any storage or treatment of hazardous substances or hazardous wastes which could have such a result), nor (D) store any hazardous wastes on or about the Property in violation of any federal or California laws or in violation of the terms of any federal or California licenses or permits held by Tenant.

(iv) Tenant shall comply with all applicable laws, rules, regulations, orders and permits relating to underground storage tanks installed by Tenant or its agents or employees or at the request of Tenant (including any installation, monitoring, maintenance, closure and/or removal of such tanks) as such tanks are defined in California Health & Safety Code § 25281(x), including, without limitation, complying with California Health & Safety Code §§ 25280-25299.7 and the regulations promulgated thereunder, as amended. Tenant shall furnish to Landlord copies of all registrations and permits issued to or held by Tenant from time to time for any and all underground storage tanks located on or under the Property.

(v) If applicable, Tenant shall provide Landlord in writing the following information and/or documentation at the commencement of this Lease and within sixty (60) days of any change in or addition to the required information and/or documentation (provided, however, that in the case of the materials described in subparagraphs (B), (C) and (E) below, Tenant shall not be required to deliver copies of such materials to Landlord but shall maintain copies of such materials to such extent and for such periods as may be required by applicable law and shall permit Landlord or its representatives to inspect and copy such materials during normal business hours at any time and from time to time upon reasonable notice to Tenant):

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(A) A list of all hazardous substances and/or wastes that Tenant receives, uses, handles, generates, transports, stores, treats or disposes of from time to time in connection with its operations on the Property.

(B) All Material Safety Data Sheets (“MSDS’s”), if any, required to be completed with respect to operations of Tenant at the Property from time to time in accordance with Title 26, California Code of Regulations § 8-5194 or 42 U.S.C. § 11021, or any amendments thereto, and any Hazardous Materials Inventory Sheets that detail the MSDS’s.

(C) All hazardous waste manifests (as defined in Title 26, California Code of Regulations § 22-66481), if any, that Tenant is required to complete from time to time in connection with its operations at the Property.

(D) A copy of any Hazardous Materials Management Plan required from time to time with respect to Tenant’s operations at the Property, pursuant to California Health & Safety Code §§ 25500 et seq., and any regulations promulgated thereunder, as amended.

(E) Copies of any Contingency Plans and Emergency Procedures required of Tenant from time to time due to its operations in accordance with Title 26, California Code of Regulations §§ 22-67140 et seq., and any amendments thereto, and copies of any Training Programs and Records required under Title 26, California Code of Regulations, § 22-67105, and any amendments thereto.

(F) Copies of any biennial reports required to be furnished to the California Department of Health Services from time to time relating to hazardous substances or wastes, pursuant to Title 26, California Code of Regulations, § 22-66493, and any amendments thereto.

(G) Copies of all industrial wastewater discharge permits issued to or held by Tenant from time to time in connection with its operations on the Property.

(H) Copies of any other lists or inventories of hazardous substances and/or wastes on or about the Property that Tenant is otherwise required to prepare and file from time to time with any governmental or regulatory authority.

. (vi) Tenant shall secure Landlord’s prior written approval for any proposed receipt, storage, possession, use, transfer or disposal of “radioactive materials”, or “radiation,” as such materials are defined in Title 26, California Code of Regulations § 1730100, and/or any other materials possessing the characteristics of the materials so defined, which approval Landlord may withhold in its sole and absolute discretion; provided, that such approval shall not be required for any radioactive materials (x) for which Tenant has secured prior written approval of the Nuclear Regulatory Commission and delivered to Landlord a copy of such approval (if applicable), or (y) which Tenant is authorized to use pursuant to the terms of a Radioactive Material License (if any) issued by the State of California, provided that Tenant has delivered a copy of such License to Landlord. Tenant, in connection with any such authorized receipt, storage, possession, use, transfer or disposal of radioactive materials or radiation, shall:

(A) Comply with all federal, state and local laws, rules, regulations, orders, licenses and permits issued to or applicable to Tenant with respect to its business operations on the Property;

(B) Maintain, to such extent and for such periods as may be required by applicable law, and permit Landlord or its representatives to inspect during normal business hours at any time and from time to time upon reasonable notice to Tenant, a list of all radioactive materials or radiation received, stored, possessed, used, transferred or disposed of from time to time, to the extent not already disclosed through delivery of a copy of a Nuclear Regulatory Commission approval and/or a California Radioactive Material License with respect thereto as contemplated above; and

(C) Maintain, to such extent and for such periods as may be required by applicable law, and permit Landlord or its representatives to inspect during normal business hours at any time and from time to time upon reasonable notice to Tenant, all licenses. registration materials, inspection reports, governmental orders and permits in connection with the receipt, storage, possession, use, transfer or disposal of radioactive materials or radiation by Tenant or in connection with the operation of Tenant’s business on the Property from time to time.

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(vii) Tenant shall comply with any and all applicable laws, rules, regulations and orders of any governmental authority with respect to the release into the environment of any hazardous wastes or substances or radiation or radioactive materials by Tenant or its agents or employees. Tenant shall give Landlord immediate verbal notice of any unauthorized release of any such hazardous wastes or substances or radiation or radioactive materials into the environment, and to follow such verbal notice with written notice to Landlord of such release within twenty-four (24) hours of the time at which Tenant became aware of such release.

(viii) Tenant shall indemnify, defend and hold Landlord harmless from and against any and all claims, losses (including, but not limited to, loss of rental income and loss due to business interruption), damages, liabilities, costs, legal fees and expenses of any sort arising out of or relating to (A) any failure by Tenant to comply with any of its obligations under this Section 13.6(b), or (B) any receipt, use handling, generation, transportation, storage, treatment, release and/or disposal of any hazardous substance or waste or any radioactive material or radiation on or about the Property in connection with Tenant’s use or occupancy of the Property or as a result of any intentional or negligent acts or omissions of Tenant or of any agent, employee or invitee of Tenant.

(ix) Tenant shall cooperate with Landlord in furnishing Landlord with complete information regarding Tenant’s receipt, handling, use, storage, transportation, generation, treatment and/or disposal of any hazardous substances or wastes or radiation or radioactive materials. Upon request, Tenant agrees to grant Landlord reasonable access at reasonable times to the Property to inspect Tenant’s receipt, handling, use, storage, transportation, generation, treatment and/or disposal of hazardous substances or wastes or radiation or radioactive materials, without being deemed guilty of any disturbance of Tenant’s use or possession and without being liable to Tenant in any manner.

(x) Notwithstanding Landlord’s rights of inspection and review under this Section 13.6(b), Landlord shall have no obligation or duty to so inspect or review, and no third party shall be entitled to rely on Landlord to conduct any sort of inspection or review by reason of the provisions of this Section 13.6(b).

(xi) If Tenant or its employees, agents, contractors, vendors, customers or guests receive, handle, use, store, transport, generate, treat and/or dispose of any hazardous substances or wastes or radiation or radioactive materials on or about the Property at any time during the term of this Lease, then within thirty (30) days after termination or expiration of this Lease, Tenant at its sole cost and expense shall obtain and deliver to Landlord an environmental study, performed by an expert reasonably satisfactory to Landlord, evaluating the presence or absence of hazardous substances and wastes, radiation and radioactive materials an and about the Property. Such study shall be based on a reasonable and prudent level of tests and investigations of the Buildings and other appropriate portions of the Property (if any), which tests shall be conducted no earlier than the date of termination or expiration of this Lease. Liability for any remedial actions required or recommended on the basis of such study shall be allocated in accordance with Sections 13.4,13.6,14.6 and other applicable provisions of this Lease.

(c) Landlord shall indemnify, defend and hold Tenant harmless from and against any and all claims, losses, damages, liabilities, costs, legal fees and expenses of any sort arising out of or relating to (i) the presence on the Property of any hazardous substances or wastes or radiation or radioactive materials present on the Property as of the first Rent Commencement Date to occur hereunder (other than as a result of any intentional or negligent acts or omissions of Tenant or of any agent, employee or invitee of Tenant), and/or (ii) any unauthorized release into the environment (including, but not limited to, the Property) of any hazardous substances or wastes or radiation or radioactive materials to the extent such release results from the negligence of or willful misconduct or omission by Landlord or its agents or employees.

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(d) In the event of any third-party claims, losses, damages, liabilities, costs, legal fees and expenses of any sort (including, but not limited to, costs incurred with respect to any government-mandated remediation), against either Landlord or Tenant or both, arising out of or relating to (i) the presence on the Property of any hazardous substances or wastes or radiation or radioactive materials not present on the Property as of the first Rent Commencement Date to occur (except to the extent the presence thereof is already covered by an express indemnification obligation under Section 13.6(b)(viii) or Section 13.6(c), as applicable), and/or (ii) any unauthorized release into the environment (including, but not limited to, the Property) of any hazardous substances or wastes or radiation or radioactive materials (except to the extent such release is already covered by an express indemnification obligation under Section 13.6(b)(viii) or Section 13.6(c), as applicable), then (x) Landlord and Tenant shall cooperate reasonably and in good faith in the defense of such third-party claims, liabilities and related matters and (y) Landlord and Tenant shall each bear fifty percent (50%) of the total claims, losses, damages, liabilities, costs, legal fees and expenses incurred by Landlord and/or Tenant in connection with matters covered by this Section 13.6(d). For purposes of the sharing of expenses contemplated in clause (y) of the preceding sentence, the party directly paying or incurring such costs or expenses shall be entitled to invoice the other party from time to time (on a monthly basis or at other appropriate intervals) for such other party’s respective share thereof, which invoice shall be accompanied by copies of third-party invoices or other reasonable documentation supporting the invoiced amounts, and the party receiving such invoice shall pay its share as reflected in the applicable invoice within fifteen (15) days after receipt thereof, unless the parties agree otherwise. Within three (3) months after receipt of any such invoice, the party receiving the invoice shall be entitled, upon reasonable written notice and during normal business hours, to inspect and examine the books and records of the party submitting the invoice with respect to the invoiced amounts. Any dispute with respect thereto that the parties are unable to resolve by good faith negotiations shall be resolved by an independent audit using the same procedure set forth in Section 9.3(b).

(e) The provisions of this Section 13.6 shall survive the termination of this Lease.

14. INSURANCE AND INDEMNITY

14.1 Liability and Property Insurance.

(a) Tenant shall procure and maintain in full force and effect at all times during the term of this Lease, at Tenant’s cost and expense, commercial general liability insurance to protect against liability arising out of or related to the use of or resulting from any accident occurring in, upon or about the Property, with combined single limit of liability of not less than Five Million Dollars ($5,000,000) per occurrence for bodily injury and property damage. Such insurance shall name Landlord, its Manager, its property manager and any lender holding a deed of trust on the Property from time to time (as designated in writing by Landlord to Tenant from time to time) as additional insureds thereunder. The amount of such insurance shall not be construed to limit any liability or obligation of Tenant under this Lease. Tenant shall also procure and maintain in full force and effect at all times during the term of this Lease, at Tenant’s cost and expense, products/completed operations coverage on terms and in amounts satisfactory to Landlord in its reasonable discretion.

(b) Landlord shall procure and maintain in full force and effect at all times during the term of this Lease, at Landlord’s cost and expense (but reimbursable as an Operating Expense under Section 9.2 hereof), commercial general liability insurance to protect against liability arising out of or related to the use of or resulting from any accident occurring in, upon or about the Property, with combined single limit of liability of not less than Five Million Dollars ($5,000,000) per occurrence for bodily injury and property damage.

(c) Landlord shall procure and maintain in full force and effect at all times during the term of this Lease, at Landlord’s cost and expense (but reimbursable as an Operating Expense under Section 9.2 hereof), policies of property insurance providing protection against “all risk of direct physical loss” (as defined by and detailed in the Insurance Service Office’s Commercial Property Program “Cause of Loss – Special Form [CP 1030]” or its equivalent) for the Building Shell (as defined in the Workletter) of each Building and for the improvements in the Common Areas of the Property, on a full replacement cost basis (with no co-insurance or, if

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coverage without co-insurance is not reasonably available, then on an “agreed amount” basis). Such insurance shall include earthquake and environmental coverage and shall have such commercially reasonable deductibles and other terms as Landlord in its reasonable discretion determines to be appropriate. Landlord shall, in all events, have no obligation to insure the Tenant Improvements or any other alterations, additions or improvements installed by Tenant in the Buildings or on or about the Property; provided, however, that if Tenant so requests in writing, Landlord agrees to include the Tenant Improvements under Landlord’s earthquake coverage, in which event (i) such earthquake coverage with respect to the Tenant Improvements shall be in such amounts and with such commercially reasonable deductibles and other terms as Landlord and Tenant may mutually and reasonably determine to be appropriate, (ii) such earthquake coverage shall, in Landlord’s discretion, either name both Landlord and Tenant as insureds as their interests may appear or name Tenant as an additional insured with respect to the portion of the policy that provides earthquake coverage for the Tenant Improvements, (iii) the cost of such earthquake coverage for the Tenant Improvements shall be charged back to Tenant as additional rent under this Lease and shall be reimbursed by Tenant to Landlord within ten (10) business days after Tenant’s receipt of a written invoice from Landlord with respect to the premium costs attributable to such coverage, (iv) Tenant shall provide to Landlord from time to time, at or about the Rent Commencement Date for the applicable Building and thereafter annually or at such intervals as Landlord may reasonably request, an updated schedule of values or other appropriate information with respect to the insurable value of the Tenant Improvements, and (v) Landlord shall have no obligation or liability with respect to any underinsurance of the Tenant Improvements that results from Tenant’s failure to keep Landlord informed on a current basis of the insurable value of such Tenant Improvements from time to time.

(d) Tenant shall procure and maintain in full force and effect at all times during the term of this Lease, at Tenant’s cost and expense, policies of property insurance providing protection against “all risk of direct physical loss” (as defined by and detailed in the Insurance Service Office’s Commercial Property Program “Cause of Loss – Special Form [CP1030]” or its equivalent) for the Tenant Improvements constructed by Tenant pursuant to the Workletter and on all other alterations, additions and improvements installed by Tenant from time to time in or about the Building, on a full replacement cost basis (with no co-insurance or, if coverage without co-insurance is not reasonably available, then on an “agreed amount” basis). Such insurance may have such commercially reasonable deductibles and other terms as Tenant in its reasonable discretion determines to be appropriate, and shall name both Tenant and Landlord as insureds as their interests may appear. Without limiting the generality of the foregoing provisions, Tenant’s property insurance on the Tenant Improvements in each Building shall in all events include (i) earthquake insurance (except as otherwise provided in paragraph (c) above, if applicable) in an amount at least equal to the amount of the Tenant Improvement Allowance paid by Landlord pursuant to the Workletter in connection with the construction of the Tenant Improvements in such Building, and (ii) business interruption (income) coverage, including extra expense coverage and off-premises utility interruption coverage, in such amounts and on such terms as Tenant in its reasonable discretion determines to be appropriate.

(e) During the course of construction of the improvements being constructed by Landlord and Tenant under Section 5.1 and the Workletter, Landlord shall procure and maintain in full force and effect, at its sole cost and expense, a policy or policies of builder’s risk insurance on both the improvements being constructed by it and the improvements being constructed by Tenant, (i) in such amounts and with such commercially reasonable deductibles and other terms as Landlord in its reasonable discretion determines to be appropriate with respect to the insurance on the improvements being constructed by Landlord, and (ii) in such amounts and with such commercially reasonable deductibles and other terms as Landlord and Tenant may mutually and reasonably determine to be appropriate with respect to the insurance on the improvements being constructed by Tenant. Such insurance shall, in Landlord’s discretion, either name both Landlord and Tenant as insureds as their interests may appear or name Tenant as an additional insured with respect to the portion of the policy that covers the improvements being constructed by Tenant. Tenant shall provide to Landlord from time to time during the course of construction of improvements by Tenant, at such intervals as Landlord may reasonably request, an updated schedule of values or other appropriate information with respect to the insurable value of the improvements, work in progress and materials located on the Property in connection with Tenant’s construction of improvements, and Landlord shall have no obligation or liability with respect to any underinsurance of Tenant’s improvements, work in progress and materials that results from Tenant’s failure to keep Landlord informed on a current basis, during the course of construction, of the insurable value of such improvements, work in progress and materials on the Property from time to time.

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14.2 Quality Of Policies And Certificates. All policies of insurance required hereunder shall be issued by responsible insurers and, in the case of policies carried or required to be carried by Tenant, shall be written as primary policies not contributing with and not in excess of any coverage that Landlord may carry. The coverage provided by such policies shall include, where applicable, the clause or endorsement referred to in Section 14.4. Each party shall deliver to the other party certificates of insurance showing that the insuring party’s required policies are in effect. If either party fails to acquire, maintain or renew any insurance required to be maintained by it under this Article 14 or to pay the premium therefor, then the other party, at its option and in addition to its other remedies, but without obligation so to do, may procure such insurance, and any sums expended by Landlord to procure any such insurance on behalf of or in place of Tenant shall be repaid upon demand, with interest as provided in Section 3.2 hereof. Tenant shall give Landlord at least thirty (30) days prior written notice of any cancellation or nonrenewal of insurance required to be maintained by Tenant under this Article 14, and shall obtain written undertakings from each insurer under policies required to be maintained by Tenant to notify all insureds thereunder at least thirty (30) days prior to cancellation of coverage.

14.3 Workers’ Compensation. Tenant shall maintain in full force and effect during the term of this Lease workers’ compensation insurance, in at least the minimum amounts required by law, covering all of Tenant’s employees working on the Property.

14.4 Waiver Of Subrogation. To the extent permitted by law and without affecting the coverage provided by insurance required to be maintained hereunder, Landlord and Tenant each waive any right to recover against the other with respect to (i) damage to property, (ii) damage to the Property or any part thereof, or (iii) claims arising by reason of any of the foregoing, but only to the extent that any of the foregoing damages and claims under clauses (i)-(iii) hereof are covered, and only to the extent of such coverage, by property insurance actually carried or required to be carried hereunder by either Landlord or Tenant. This provision is intended to waive fully, and for the benefit of each party, any rights and claims which might give rise to a right of subrogation in any insurance carrier. Each party shall procure a clause or endorsement on any property insurance policy denying to the insurer rights of subrogation against the other party to the extent rights have been waived by the insured prior to the occurrence of injury or loss. Coverage provided by insurance maintained by Tenant shall not be limited, reduced or diminished by virtue of the subrogation waiver herein contained.

14.5 Increase In Premiums. Tenant shall do all acts and pay all expenses necessary to insure that the Buildings are not used for purposes prohibited by any applicable fire insurance, and that Tenant’s use of the Buildings and the Property complies with all requirements necessary to obtain any such insurance. If Tenant uses or permits the Buildings or the Property to be used in a manner which increases the existing rate of any insurance carried by Landlord on the Center, then Tenant shall pay the amount of the increase in premium caused thereby, and Landlord’s costs of obtaining other replacement insurance policies, including any increase in premium, within ten (10) days after demand therefor by Landlord.

14.6 Indemnification.

(a) Except as otherwise expressly provided in this Lease, Tenant shall indemnify, defend and hold Landlord and its members, partners, shareholders, officers, directors, agents, employees and contractors harmless from any and all liability for bodily injury to or death of any person, or loss of or damage to the property of any person, and all actions, claims, demands, costs (including, but not limited to, reasonable attorneys’ fees), damages or expenses of any kind arising therefrom which may be brought or made against Landlord or which Landlord may pay or incur by reason of the use, occupancy and enjoyment of the Property by Tenant or any invitees, sublessees, licensees, assignees, agents, employees or contractors of Tenant or holding under Tenant (including, but not limited to, any such matters arising out of or in connection with any early entry upon the Property by Tenant pursuant to Section 2.2 hereof) from any cause whatsoever other than negligence or willful misconduct or omission by Landlord or its agents, employees or contractors. Landlord and its members, partners, shareholders, officers, directors, agents, employees and contractors shall not be liable for, and Tenant hereby waives all claims against such persons for, damages to goods, wares and merchandise in or upon the Property, or for injuries to Tenant, its agents or third persons in or upon the Property, from any cause whatsoever other than negligence or willful misconduct or omission by Landlord or its agents, employees or contractors. Tenant shall give prompt notice to Landlord of any casualty or accident in, on or about the Property.

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(b) Except as otherwise expressly provided in this Lease, Landlord shall indemnify, defend and hold Tenant and its shareholders, officers, directors, agents, employees and contractors harmless from any and all liability for bodily injury to or death of any person, or loss of or damage to the property of any person, and all actions, claims, demands, costs (including, but not limited to, reasonable attorneys’ fees), damages or expenses of any kind arising therefrom which may be brought or made against Tenant or which Tenant may pay or incur, to the extent such liabilities or other matters arise in, on or about the Property by reason of any negligence or willful misconduct or omission by Landlord or its agents, employees or contractors.

14.7 Blanket Policy. Any policy required to be maintained hereunder may be maintained under a so-called “blanket policy” insuring other parties and other locations so long as the amount of insurance required to be provided hereunder is not thereby diminished. Without limiting the generality of the requirement set forth at the end of the preceding sentence, property insurance provided under a blanket policy shall provide full replacement cost coverage and liability insurance provided under a blanket policy shall include per location aggregate limits meeting or exceeding the limits required under this Article 14.

15. SUBLEASE AND ASSIGNMENT

15.1 Assignment And Sublease Of Building(s). Except in the case of a Permitted Transfer (as hereinafter defined), Tenant shall not have the right or power to assign its interest in this Lease, or make any sublease of any Building or any portion thereof, nor shall any interest of Tenant under this Lease be assignable involuntarily or by operation of law, without on each occasion obtaining the prior written consent of Landlord, which consent shall not be unreasonably withheld or delayed. Any purported sublease or assignment of Tenant’s interest in this Lease requiring but not having received Landlord’s consent thereto (to the extent such consent is required hereunder) shall be void. Without limiting the generality of the foregoing provisions, Landlord may withhold consent to any proposed subletting or assignment solely on the ground, if applicable, that the use by the proposed subtenant or assignee is reasonably likely to be incompatible with Landlord’s use of the balance of the Property or of any adjacent property owned or operated by Landlord, unless the proposed use is within the permitted uses specified in Section 13.1, in which event it shall not be reasonable for Landlord to object to the proposed use. Except in the case of a Permitted Transfer, any dissolution, consolidation, merger or other reorganization of Tenant, or any sale or transfer of the stock or assets of or other interest in Tenant, in a single transaction or series of related transactions, involving in the aggregate a change of fifty percent (50%) or more in the beneficial ownership of Tenant or its assets shall be deemed to be an assignment hereunder and shall be void without the prior written consent of Landlord as required above. Notwithstanding the foregoing, (i) an initial public offering of the common stock of Tenant shall not be deemed to be an assignment hereunder; and (ii) Tenant shall have the right to assign this Lease or sublet the Buildings, or any portion thereof, without Landlord’s consent (but with prior or concurrent written notice by Tenant to Landlord), to any entity which controls, is controlled by, or is under common control with Tenant, or to any entity which results from a merger or consolidation with Tenant, or to any entity engaged in a bona fide joint venture with Tenant, or to any entity which acquires substantially all of the stock or assets of Tenant, as a going concern, with respect to the business that is being conducted on the Property (hereinafter each a “Permitted Transfer”). In addition, a sale or transfer of the capital stock of Tenant shall be deemed a Permitted Transfer (x) if such sale or transfer occurs in connection with any bona fide financing or capitalization for the benefit of Tenant, or (y) if Tenant becomes, and while Tenant is, a publicly traded corporation. Landlord shall have no right to terminate this Lease in connection with, and shall have no right to any sums or other economic consideration resulting from, any Permitted Transfer. Except as expressly set forth in this Section 15.1, however, the provisions of Section 15.2 shall remain applicable to any Permitted Transfer and the transferee under such Permitted Transfer shall be and remain subject to all of the terms and provisions of this Lease.

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15.2 Rights Of Landlord. Consent by Landlord to one or more assignments of this Lease, or to one or more sublettings of any Building or any portion thereof, or collection of rent by Landlord from any assignee or sublessee, shall not operate to exhaust Landlord’s rights under this Article 15, nor constitute consent to any subsequent assignment or subletting. No assignment of Tenant’s interest in this Lease and no sublease shall relieve Tenant of its obligations hereunder, notwithstanding any waiver or extension of time granted by Landlord to any assignee or sublessee, or the failure of Landlord to assert its rights against any assignee or sublessee, and regardless of whether Landlord’s consent thereto is given or required to be given hereunder. In the event of a default by any assignee, sublessee or other successor of Tenant in the performance of any of the terms or obligations of Tenant under this Lease, Landlord may proceed directly against Tenant without the necessity of exhausting remedies against any such assignee, sublessee or other successor. In addition, Tenant immediately and irrevocably assigns to Landlord, as security for Tenant’s obligations under this Lease, all rent from any subletting of all or a part of any Building as permitted under this Lease, and Landlord, as Tenant’s assignee and as attorney-in-fact for Tenant, or any receiver for Tenant appointed on Landlord’s application, may collect such rent and apply it toward Tenant’s obligations under this Lease; except that, until the occurrence of an act of default by Tenant, Tenant shall have the right to collect such rent and to retain all sublease profits.

16. RIGHT OF ENTRY AND QUIET ENJOYMENT

16.1 Right Of Entry. Landlord and its authorized representatives shall have the right to enter the Buildings at any time during the term of this Lease during normal business hours and upon not less than twenty-four (24) hours prior notice, except in the case of emergency (in which event no notice shall be required and entry may be made at any time), for the purpose of inspecting and determining the condition of the Buildings or for any other proper purpose including, without limitation, to make repairs, replacements or improvements which Landlord may deem necessary, to show the Buildings to prospective purchasers, to show the Buildings to prospective tenants (but only during the final year of the term of this Lease), and to post notices of nonresponsibility. Landlord shall not be liable for inconvenience, annoyance, disturbance, loss of business, quiet enjoyment or other damage or loss to Tenant by reason of making any repairs or performing any work upon the Buildings or the Property or by reason of erecting or maintaining any protective barricades in connection with any such work, and the obligations of Tenant under this Lease shall not thereby be affected in any manner whatsoever, provided, however, Landlord shall use reasonable efforts to minimize the inconvenience to Tenant’s normal business operations caused thereby.

16.2 Quiet Enjoyment. Landlord covenants that Tenant, upon paying the rent and performing its obligations hereunder and subject to all the terms and conditions of this Lease, shall peacefully and quietly have, hold and enjoy the Buildings and the Property throughout the term of this Lease, or until this Lease is terminated as provided by this Lease.

17. CASUALTY AND TAKING

17.1 Damage or Destruction.

(a) If any or all Buildings, or the Common Areas of the Property necessary for Tenant’s use and occupancy of any or all Buildings, are damaged or destroyed in whole or in part under circumstances in which (i) repair and restoration is permitted under applicable governmental laws, regulations and building codes then in effect and (ii) repair and restoration reasonably can be completed within a period of one (1) year (or, in the case of an occurrence during the last two (2) years of the term of this Lease, within a period of sixty (60) days) following the date of the occurrence, then Landlord, as to the Common Areas of the Property and the Building Shell of the applicable Building(s), and Tenant, as to the Tenant Improvements constructed by Tenant, shall commence and complete, with all due diligence and as promptly as is reasonably practicable under the conditions then existing, all such repair and restoration as may be required to return the affected portions of the Property to a condition comparable to that existing immediately prior to the occurrence. In the event of damage or destruction the repair of which is not permitted under applicable governmental laws, regulations and building codes then in effect, if such damage or destruction (despite being corrected to the extent then permitted under applicable governmental laws, regulations and building codes) would still materially impair Tenant’s ability to conduct its business in the applicable Building(s), then either party may terminate this Lease with respect to the applicable Building(s) as of the date of the

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occurrence by giving written notice to the other within thirty (30) days after the date of the occurrence; if neither party timely elects such termination, or if such damage or destruction does not materially impair Tenant’s ability to conduct its business in the applicable Building(s), then this Lease shall continue in full force and effect, except that there shall be an equitable adjustment in monthly minimum rental and of Tenant’s Operating Cost Share of Operating Expenses, based upon the extent to which Tenant’s ability to conduct its business in the applicable Building(s) is impaired, and Landlord and Tenant respectively shall restore the Common Areas and Building Shell and the Tenant Improvements in the applicable Building(s) to a complete architectural whole and to a functional condition. In the event of damage or destruction which cannot reasonably be repaired within one (1) year (or, in the case of an occurrence during the last two (2) years of the term of this Lease, within a period of sixty (60) days) following the date of the occurrence, then either Landlord or Tenant, at its election, may terminate this Lease with respect to the applicable Building(s) as of the date of the occurrence by giving written notice to the other within thirty (30) days after the date of the occurrence; if neither party timely elects such termination, then this Lease shall continue in full force and effect and Landlord and Tenant shall each repair and restore applicable portions of the Property in accordance with the first sentence of this Section 17.1(a).

(b) The respective obligations of Landlord and Tenant pursuant to Section 17.1(a) are subject to the following limitations:

(i) If the occurrence results from a peril which is required to be insured pursuant to Section 14.1(c) and (d) above, the obligations of each party shall not exceed the amount of insurance proceeds received from insurers (or, in the case of any failure to maintain required insurance, proceeds that reasonably would have been available if the required insurance had been maintained) by reason of such occurrence, plus the amount of the party’s permitted deductible (provided that each party shall be obligated to use its best efforts to recover any available proceeds from the insurance which it is required to maintain pursuant to the provisions of Section 14.1(c) or (d), as applicable), and, if such proceeds (including, in the case of a failure to maintain required insurance, any proceeds that reasonably would have been available) are insufficient, either party may terminate this Lease with respect to the applicable Building(s) unless the other party promptly elects and agrees, in writing, to contribute the amount of the shortfall; and

(ii) If the occurrence results from a peril which is not required to be insured pursuant to Section 14.1(c) and (d) above and is not actually insured, Landlord shall be required to repair and restore the Common Areas and the Building Shell of the applicable Building(s) to the extent necessary for Tenant’s continued use and occupancy of the applicable Building(s), and Tenant shall be required to repair and restore the Tenant Improvements to the extent necessary for Tenant’s continued use and occupancy of the applicable Building(s), provided that each party’s out of pocket cost (after application of any insurance proceeds) to repair and restore shall not exceed an amount equal to fifteen percent (15%) of the replacement cost of the Building Shell of the applicable Building(s) and the Common Area improvements, as to Landlord, or fifteen percent (15%) of the replacement cost of the Tenant Improvements in the applicable Building(s), as to Tenant; if the out of pocket replacement cost as to either party exceeds such amount, then the party whose limit has been exceeded may terminate this Lease with respect to the applicable Building(s) unless the other party promptly elects and agrees, in writing, to contribute the amount of the shortfall.

(c) If this Lease is terminated with respect to the applicable Building(s) pursuant to the foregoing provisions of this Section 17.1 following an occurrence which is a peril actually insured or required to be insured against pursuant to Section 14.1(c) and (d), Landlord and Tenant agree (and any Lender shall be asked to agree) that such insurance proceeds shall be allocated between Landlord and Tenant in a manner which fairly and reasonably reflects their respective ownership rights under this Lease, as of the termination or expiration of the term of this Lease, with respect to the improvements, fixtures, equipment and other items to which such insurance proceeds are attributable.

(d) From and after the date of an occurrence resulting in damage to or destruction of a Building or of the Common Areas necessary for Tenant’s use and occupancy of the Buildings, and continuing until repair and restoration thereof are completed, there shall be an equitable abatement of Minimum Rental and additional rent and of Tenant’s Operating Cost Share of Operating Expenses based upon the degree to which Tenant’s ability to conduct its business in the applicable Building(s) is impaired.

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17.2 Condemnation.

(a) If during the term of this Lease one or more Buildings, the Property or Improvements, or any substantial part of any of them, is taken by eminent domain or by reason of any public improvement or condemnation proceeding, or in any manner by exercise of the right of eminent domain (including any transfer in avoidance of an exercise of the power of eminent domain), or receives irreparable damage by reason of anything lawfully done under color of public or other authority, then (i) this Lease shall terminate as to the entire applicable Building(s) at Landlord’s election by written notice given to Tenant within sixty (60) days after the taking has occurred, and (ii) this Lease shall terminate as to the entire applicable Building(s) at Tenant’s election, by written notice given to Landlord within thirty (30) days after the nature and extent of the taking have been finally determined, if the portion of the Property taken is of such extent and nature as substantially to handicap, impede or permanently impair Tenant’s use of the balance of the applicable Building(s). If Tenant elects to terminate this Lease, Tenant shall also notify Landlord of the date of termination, which date shall not be earlier than thirty (30) days nor later than ninety (90) days after Tenant has notified Landlord of Tenant’s election to terminate, except that this Lease shall terminate on the date of taking if such date falls on any date before the date of termination designated by Tenant. If neither party elects to terminate this Lease as to the applicable Building(s) as hereinabove provided, this Lease shall continue in full force and effect (except that there shall be an equitable abatement of Minimum Rental and additional rent and of Tenant’s Operating Cost Share of Operating Expenses based upon the degree to which Tenant’s ability to conduct its business in the applicable. Building(s) is impaired), Landlord shall restore the Building Shell of the applicable Building(s) and the Common Area improvements to a complete architectural whole and a functional condition and as nearly as reasonably possible to the condition existing before the taking, and Tenant shall restore the Tenant Improvements and Tenant’s other alterations, additions and improvements to a complete architectural whole and a functional condition and as nearly as reasonably possible to the condition existing before the taking. In connection with any such restoration, each party shall use its respective best efforts (including, without limitation, any necessary negotiation or intercession with its respective lender, if any) to ensure that any severance damages or other condemnation awards intended to provide compensation for rebuilding or restoration costs are promptly collected and made available to Landlord and Tenant in portions reasonably corresponding to the cost and scope of their respective restoration obligations, subject only to such payment controls as either party or its lender may reasonably require in order to ensure the proper application of such proceeds toward the restoration of the Improvements. Each party waives the provisions of Code of Civil Procedure Section 1265.130, allowing either party to petition the Superior Court to terminate this Lease in the event of a partial condemnation of one or more Buildings or the Property.

(b) The respective obligations of Landlord and Tenant pursuant to Section 17.2(a) are subject to the following limitations:

(i) Each party’s obligation to repair and restore shall not exceed, net of any condemnation awards or other proceeds available for and allocable to such restoration as contemplated in Section 17.2(a), an amount equal to five percent (5%) of the replacement cost of the Building Shell of the applicable Building(s) and the Common Area improvements, as to Landlord, or five percent (5%) of the replacement cost of the Tenant Improvements in the applicable Building(s), as to Tenant; if the replacement cost as to either party exceeds such amount, then the party whose limit has been exceeded may terminate this Lease with respect to the applicable Building(s) unless the other party promptly elects and agrees, in writing, to contribute the amount of the shortfall; and

(ii) If this Lease is terminated with respect to the applicable Building(s) pursuant to the foregoing provisions of this Section 17.2, or if this Lease remains in effect but any condemnation awards or other proceeds become available as compensation for the loss or destruction of any of the Improvements, then Landlord and Tenant agree (and any Lender shall be asked to agree) that there shall be paid from such award or proceeds (i) to Landlord, the award or proceeds attributable or allocable to the Building Shell of the applicable Building(s) and/or the Common Area improvements, and (ii) to Landlord and Tenant, respectively, portions of the award or proceeds attributable or allocable to the Tenant Improvements in the applicable Building(s), in the respective proportions in which Landlord and Tenant would have shared, under Section 17.1(c), the proceeds of any insurance proceeds following loss or destruction of such Tenant Improvements by an insured casualty.

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17.3 Reservation Of Compensation. Landlord reserves, and Tenant waives and assigns to Landlord, all rights to any award or compensation for damage to the Improvements, the Property and the leasehold estate created hereby, accruing by reason of any taking in any public improvement, condemnation or eminent domain proceeding or in any other manner by exercise of the right of eminent domain or of anything lawfully done by public authority, except that (a) Tenant shall be entitled to any and all compensation or damages paid for or on account of Tenant’s moving expenses, trade fixtures and equipment, and (b) any condemnation awards or proceeds described in Section 17.2(b)(ii) shall be allocated and disbursed in accordance with the provisions of Section 17.2(b)(ii), notwithstanding any contrary provisions of this Section 17.3.

17.4 Restoration Of Improvements. In connection with any repair or restoration of Improvements by either party following a casualty or taking as hereinabove set forth, the party responsible for such repair or restoration shall, to the extent possible, return such Improvements to a condition substantially equal to that which existed immediately prior to the casualty or taking. To the extent such party wishes to make material modifications to such Improvements, such modifications shall be subject to the prior written approval of the other party (not to be unreasonably withheld or delayed), except that no such approval shall be required for modifications that are required by applicable governmental authorities as a condition of the repair or restoration, unless such required modifications would impair or impede Tenant’s conduct of its business in the applicable Building(s) (in which case any such modifications in Landlord’s work shall require Tenant’s consent, not unreasonably withheld or delayed) or would materially and adversely affect the exterior appearance, the structural integrity or the mechanical or other operating systems of the applicable Building(s) (in which case any such modifications in Tenant’s work shall require Landlord’s consent, not unreasonably withheld or delayed).

18. DEFAULT

18.1 Events Of Default. The occurrence of any of the following shall constitute an event of default on the part of Tenant:

(a) Abandonment. Abandonment of one or more Buildings. “Abandonment” is hereby defined to include, but is not limited to, any absence by Tenant from the applicable Building(s) for fifteen (15) consecutive days or more while Tenant is in default under any other provision of this Lease. Tenant waives any right Tenant may have to notice under Section 1951.3 of the California Civil Code, the terms of this subsection (a) being deemed such notice to Tenant as required by said Section 1951.3;

(b) Nonpayment. Failure to pay, when due, any amount payable to Landlord hereunder, such failure continuing for a period of five (5) days after written notice of such failure; provided, however, that any such notice shall be in lieu of, and not in addition to, any notice required under California Code of Civil Procedure Section 1161 et seq., as amended from time to time;

(c) Other Obligations. Failure to perform any obligation, agreement or covenant under this Lease other than those matters specified in subsection (b) hereof, such failure continuing for fifteen (15) days after written notice of such failure; provided, however, that if such failure is curable in nature but cannot reasonably be cured within such 15-day period, then Tenant shall not be in default if, and so long as, Tenant promptly (and in all events within such 15-day period) commences such cure and thereafter diligently pursues such cure to completion; and provided further, however, that any such notice shall be in lieu of, and not in addition to, any notice required under California Code of Civil Procedure Section 1161 et seq., as amended from time to time;

(d) General Assignment. A general assignment by Tenant for the benefit of creditors;

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(e) Bankruptcy. The filing of any voluntary petition in bankruptcy by Tenant, or the filing of an involuntary petition by Tenant’s creditors, which involuntary petition remains undischarged for a period of thirty (30) days. In the event that under applicable law the trustee in bankruptcy or Tenant has the right to affirm this Lease and continue to perform the obligations of Tenant hereunder, such trustee or Tenant shall, in such time period as may be permitted by the bankruptcy court having jurisdiction, cure all defaults of Tenant hereunder outstanding as of the date of the affirmance of this Lease and provide to Landlord such adequate assurances as may be necessary to ensure Landlord of the continued performance of Tenant’s obligations under this Lease. Specifically, but without limiting the generality of the foregoing, such adequate assurances must include assurances that the Buildings continue to be operated only for the use permitted hereunder. The provisions hereof are to assure that the basic understandings between Landlord and Tenant with respect to Tenant’s use of the Property and the benefits to Landlord therefrom are preserved, consistent with the purpose and intent of applicable bankruptcy laws;

(f) Receivership. The employment of a receiver appointed by court order to take possession of substantially all of Tenant’s assets or Tenant’s interest in one or more of the Buildings, if such receivership remains undissolved for a period of thirty (30) days;

(g) Attachment. The attachment, execution or other judicial seizure of all or substantially all of Tenant’s assets or Tenant’s interest in one or more of the Buildings, if such attachment or other seizure remains undismissed or undischarged for a period of thirty (30) days after the levy thereof; or

(h) Insolvency. The admission by Tenant in writing of its inability to pay its debts as they become due, the filing by Tenant of a petition seeking any reorganization or arrangement, composition, readjustment, liquidation, dissolution or similar relief under any present or future statute, law or regulation, the filing by Tenant of an answer admitting or failing timely to contest a material allegation of a petition filed against Tenant in any such proceeding or, if within thirty (30) days after the commencement of any proceeding against Tenant seeking any reorganization or arrangement, composition, readjustment, liquidation, dissolution or similar relief under any present or future statute, law or regulation, such proceeding shall not have been dismissed.

18.2 Remedies Upon Tenant’s Default.

(a) Upon the occurrence of any event of default described in Section 18.1 hereof, Landlord, in addition to and without prejudice to any other rights or remedies it may have, shall have the immediate right to re-enter the Buildings or any part thereof and repossess the same, expelling and removing therefrom all persons and property (which property may be stored in a public warehouse or elsewhere at the cost and risk of and for the account of Tenant), using such force as may be necessary to do so (as to which Tenant hereby waives any claim for loss or damage that may thereby occur). In addition to or in lieu of such re-entry, and without prejudice to any other rights or remedies it may have, Landlord shall have the right either (i) to terminate this Lease and recover from Tenant all damages incurred by Landlord as a result of Tenant’s default, as hereinafter provided, or (ii) to continue this Lease in effect and recover rent and other charges and amounts as they become due.

(b) Even if Tenant has breached this Lease and abandoned one or more Building(s), this Lease shall continue in effect for so long as Landlord does not terminate Tenant’s right to possession under subsection (a) hereof and Landlord may enforce all of its rights and remedies under this Lease, including the right to recover rent as it becomes due, and Landlord, without terminating this Lease, may exercise all of the rights and remedies of a lessor under California Civil Code Section 1951.4 (lessor may continue lease in effect after lessee’s breach and abandonment and recover rent as it becomes due, if lessee has right to sublet or assign, subject only to reasonable limitations), or any successor Code section. Acts of maintenance, preservation or efforts to relet the Building(s) or the appointment of a receiver upon application of Landlord to protect Landlord’s interests under this Lease shall not constitute a termination of Tenant’s right to possession.

(c) If Landlord terminates this Lease pursuant to this Section 18.2, Landlord shall have all of the rights and remedies of a landlord provided by Section 1951.2 of the Civil Code of the State of California, or any successor Code section, which remedies include Landlord’s right to recover from Tenant (i) the worth at the time of award of the unpaid rent and additional rent which had been earned at the time of termination, (ii) the worth at the time of award of the amount by which the unpaid rent and additional rent which would have been earned

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after termination until the time of award exceeds the amount of such rental loss that Tenant proves could have been reasonably avoided, (iii) the worth at the time of award of the amount by which the unpaid rent and additional rent for the balance of the term after the time of award exceeds the amount of such rental loss that Tenant proves could be reasonably avoided, and (iv) any other amount necessary to compensate Landlord for all the detriment proximately caused by Tenant’s failure to perform its obligations under this Lease or which in the ordinary course of things would be likely to result therefrom, including, but not limited to, the cost of recovering possession of the Buildings, expenses of reletting, including necessary repair, renovation and alteration of the Buildings, reasonable attorneys’ fees, and other reasonable costs. The “worth at the time of award” of the amounts referred to in clauses (i) and (ii) above shall be computed by allowing interest at ten percent (10%) per annum from the date such amounts accrued to Landlord. The “worth at the time of award” of the amounts referred to in clause (iii) above shall be computed by discounting such amounts at one percentage point above the discount rate of the Federal Reserve Bank of San Francisco at the time of award.

18.3 Remedies Cumulative. All rights, privileges and elections or remedies of Landlord contained in this Article 18 are cumulative and not alternative to the extent permitted by law and except as otherwise provided herein.

19. SUBORDINATION, ATTORNMENT AND SALE

19.1 Subordination To Mortgage. This Lease, and any sublease entered into by Tenant under the provisions of this Lease, shall be subject and subordinate to any ground lease, mortgage, deed of trust, sale/leaseback transaction or any other hypothecation for security now or hereafter placed upon the Buildings, the Property, the Center, or any of them, and the rights of any assignee of Landlord or of any ground lessor, mortgagee, trustee, beneficiary or leaseback lessor under any of the foregoing, and to any and all advances made on the security thereof and to all renewals, modifications, consolidations, replacements and extensions thereof; provided, however, that such subordination in the case of any future ground lease, mortgage, deed of trust, sale/leaseback transaction or any other hypothecation for security placed upon the Buildings, the Property, the Center or any of them shall be conditioned on Tenant’s receipt from the ground lessor, mortgagee, trustee, beneficiary or leaseback lessor of a Non-Disturbance Agreement in a form reasonably acceptable to Tenant confirming that so long as Tenant is not in default hereunder, Tenant’s rights hereunder shall not be disturbed by such person or entity. Moreover, Tenant’s obligations under this Lease shall be conditioned on Tenant’s receipt within thirty (30) days after mutual execution of this Lease, from any ground lessor, mortgagee, trustee, beneficiary or leaseback lessor currently owning or holding a security interest in the Property, of a Non-Disturbance Agreement in a form reasonably acceptable to Tenant confirming that so long as Tenant is not in default hereunder, Tenant’s rights hereunder shall not be disturbed by such person or entity. (Landlord hereby advises Tenant, however, that in fact there is no mortgagee, trustee, beneficiary, ground lessor or leaseback lessor holding an interest in the Property on the date of this Lease.) If any mortgagee, trustee, beneficiary, ground lessor, sale/leaseback lessor or assignee elects to have this Lease be an encumbrance upon the Property prior to the lien of its mortgage, deed of trust, ground lease or leaseback lease or other security arrangement and gives notice thereof to Tenant, this Lease shall be deemed prior thereto, whether this Lease is dated prior or subsequent to the date thereof or the date of recording thereof. Tenant, and any sublessee, shall execute such documents as may reasonably be requested by any mortgagee, trustee, beneficiary, ground lessor, sale/leaseback lessor or assignee to evidence the subordination herein set forth, subject to the conditions set forth above, or to make this Lease prior to the lien of any mortgage, deed of trust, ground lease, leaseback lease or other security arrangement, as the case may be, and if Tenant fails to do so within ten (10) days after demand from Landlord, Tenant constitutes and appoints Landlord as Tenant’s attorney-in-fact and in Tenant’s name, place and stead to do so. Upon any default by Landlord in the performance of its obligations under any mortgage, deed of trust, ground lease, leaseback lease or assignment, Tenant (and any sublessee) shall, notwithstanding any subordination hereunder, attorn to the mortgagee, trustee, beneficiary, ground lessor, leaseback lessor or assignee thereunder upon demand and become the tenant of the successor in interest to Landlord, at the option of such successor in interest, and shall execute and deliver any instrument or instruments confirming the attornment herein provided for.

19.2 Sale Of Landlord’s Interest. Upon sale, transfer or assignment of Landlord’s entire interest in the Buildings and the Property, Landlord shall be relieved of its obligations hereunder with respect to liabilities accruing from and after the date of such sale, transfer or assignment, except as otherwise expressly provided in Section 21.2 hereof.

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19.3 Estoppel Certificates. Either Tenant or Landlord (the “certifying party”) shall at any time and from time to time, within ten (10) days after written request by the other party (the “requesting party”), execute, acknowledge and deliver to the requesting party a certificate in writing stating: (i) that this Lease is unmodified and in full force and effect, or if there have been any modifications, that this Lease is in full force and effect as modified and stating the date and the nature of each modification; (ii) the date to which rental and all other sums payable hereunder have been paid; (iii) that the requesting party is not in default in the performance of any of its obligations under this Lease, that the certifying party has given no notice of default to the requesting party and that no event has occurred which, but for the expiration of the applicable time period, would constitute an event of default hereunder, or if the certifying party alleges that any such default, notice or event has occurred, specifying the same in reasonable detail; and (iv) such other matters as may reasonably be requested by the requesting party or by any institutional lender, mortgagee, trustee, beneficiary, ground lessor, sale/leaseback lessor or prospective purchaser of the Property or of Tenant’s leasehold interest therein. Any such certificate provided under this Section 19.3 may be relied upon by any lender, mortgagee, trustee, beneficiary, assignee or successor in interest to the requesting party, by any prospective purchaser, by any purchaser on foreclosure or sale, by any grantee under a deed in lieu of foreclosure of any mortgage or deed of trust on the Property, or by any other third party. Failure to execute and return within the required time any estoppel certificate requested hereunder shall be deemed to be an admission of the truth of the matters set forth in the form of certificate submitted to the certifying party for execution.

19.4 Subordination to CC&R’s. This Lease, and any permitted sublease entered into by Tenant under the provisions of this Lease, and the interests in real property conveyed hereby and thereby, shall be subject and subordinate (a) to any declarations of covenants, conditions and restrictions or other recorded restrictions affecting the Property or the Center from time to time, which may include easements, access rights and similar non-exclusive use rights and privileges in favor of appropriate third parties; provided that the terms of such declarations or restrictions are reasonable (or, to the extent they are not reasonable, are mandated by applicable law), do not materially impair Tenant’s ability to conduct the uses permitted hereunder on the Property, and do not discriminate against Tenant relative to other similarly situated tenants occupying portions of the Center, and provided further that except with Tenant’s prior written consent. Landlord shall not enter into any such future declarations of covenants, conditions and restrictions or other recorded restrictions that are applicable, by their terms, solely to one or more of the buildings occupied by or leased to Tenant under this Lease (including any buildings occupied by or leased to Tenant pursuant to Tenant’s exercise of any of the rights contained in Article 6 of this Lease) and not to any buildings occupied by or leased to other tenants in the Center or, if Tenant exercises its rights under Section 6,3 of this Lease, on the Expansion Property; (b) to the Declaration of Covenants, Conditions and Restrictions and Reciprocal Easements for Shearwater Project dated January 21,1998 and recorded on January 22, 1998 as Instrument No. 98-008277, Official Records of San Mateo County, as amended from time to time (the “Shearwater Declaration”), the provisions of which Shearwater Declaration are an integral part of this Lease; and (c) to the Covenant and Environmental Restriction dated as of January 26, 1998 and recorded on February 3, 1998 as Instrument No. 98-013813, Official Records of San Mateo County, as amended from time to time (the “Environmental Restriction”), the provisions of which Environmental Restriction are incorporated herein by this reference. Tenant agrees to execute, upon request by Landlord, any documents reasonably required from time to time to evidence the foregoing subordination.

19.5 Mortgagee Protection.

(a) If, in connection with any future ground lease, mortgage, deed of trust, sale/leaseback transaction or any other hypothecation for security placed upon the Buildings, the Property, the Center, or any of them, the ground lessor, mortgagee, trustee, beneficiary or leaseback lessor requests any changes in this Lease as a condition to its willingness to enter into or accept the ground lease, mortgage, deed of trust, sale/leaseback transaction or other hypothecation for security, then Tenant shall not unreasonably withhold or delay its consent to any such requested changes and shall execute, at the request of Landlord, an amendment to this Lease incorporating the changes thus reasonably consented to by Tenant. It shall be deemed reasonable for Tenant to withhold consent to any requested change which imposes a substantial

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new monetary obligation on Tenant or which otherwise substantially impairs Tenant’s rights under this Lease. Tenant’s obligations under this Section 19.5(a) shall be conditioned on Tenant’s concurrent receipt, from the ground lessor, mortgagee, trustee, beneficiary or leaseback lessor, of a Non-Disturbance Agreement in a form reasonably acceptable to Tenant confirming that so long as Tenant is not in default hereunder, Tenant’s rights hereunder shall not be disturbed by such person or entity.

(b) If, following a default by Landlord under any mortgage, deed of trust, ground lease, leaseback lease or other security arrangement covering the Buildings, the Property, the Center or any of them, the Buildings, the Property and/or the Center, as applicable, is acquired by the mortgagee, beneficiary, master lessor or other secured party, or by any other successor owner, pursuant to a foreclosure, trustee’s sale, sheriff’s sale, lease termination or other similar procedure (or deed in lieu thereof), then any such person or entity so acquiring the Buildings, the Property and/or the Center shall not be:

(i) liable for any act or omission of a prior landlord or owner of the Property and/or the Center (including, but not limited to, Landlord);

(ii) subject to any offsets or defenses that Tenant may have against any prior landlord or owner of the Property and/or the Center (including, but not limited to, Landlord);

(iii) bound by any rent or additional rent that Tenant may have paid in advance to any prior landlord or owner of the Property and/or the Center (including, but not limited to, Landlord) for a period in excess of one month, or by any security deposit, cleaning deposit or other prepaid charge that Tenant may have paid in advance to any prior landlord or owner (including, but not limited to, Landlord) except to the extent such deposit or prepaid amount has been expressly turned over to or credited to the successor owner thus acquiring the Property and/or the Center, as applicable;

(iv) liable for any warranties or representations of any nature whatsoever, whether pursuant to this Lease or otherwise, by any prior landlord or owner of the Property and/or the Center (including, but not limited to, Landlord) with respect to the use, construction, zoning, compliance with laws, title, habitability, fitness for purpose or possession, or physical condition (including, without limitation, environmental matters) of the Property, the Buildings or the Center; or

(v) liable to Tenant in any amount beyond the interest of such mortgagee, beneficiary, master lessor or other secured party or successor owner in the Property and the Center as they exist from time to time, it being the intent of this provision that Tenant shall look solely to the interest of any such mortgagee, beneficiary, master lessor or other secured party or successor owner in the Property and Center for the payment and discharge of the landlord’s obligations under this Lease and that such mortgagee, beneficiary, master lessor or other secured party or successor owner shall have no separate personal liability for any such obligations.

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21. MISCELLANEOUS

21.1 Notices. All notices, consents, waivers and other communications which this Lease requires or permits either party to give to the other shall be in writing and shall be deemed given when delivered personally (including delivery by private same-day or overnight courier or express delivery service) or by telecopier with mechanical confirmation of transmission, effective upon personal delivery to or refusal of delivery by the recipient (in the case of personal delivery by any of the means described above) or upon telecopier transmission during normal business hours at the recipient’s office (in the case of telecopier transmission, with any transmission outside of normal business hours being effective as of the beginning of the first business day commencing after the time of actual transmission) to the parties at their respective addresses as follows:

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or to such other address as may be contained in a notice at least fifteen (15) days prior to the address change from either party to the other given pursuant to this Section. Rental payments and other sums required by this Lease to be paid by Tenant shall be delivered to Landlord in care of Britannia Management Services, Inc. at the address provided above in this Section, or to such other address as Landlord may from time to time specify in writing to Tenant, and shall be deemed to be paid only upon actual receipt.

21.2 Successors And Assigns. The obligations of this Lease shall run with the land, and this Lease shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns, except that the original Landlord named herein and each successive Landlord under this Lease shall be liable only for obligations accruing during the period of its ownership of the Property, said liability terminating upon termination of such ownership and passing to the successor lessor.

21.3 No Waiver. The failure of Landlord to seek redress for violation, or to insist upon the strict performance, of any covenant or condition of this Lease shall not be deemed a waiver of such violation, or prevent a subsequent act which would originally have constituted a violation from having all the force and effect of an original violation.

21.4 Severability. If any provision of this Lease or the application thereof is held to be invalid or unenforceable, the remainder of this Lease or the application of such provision to persons or circumstances other than those as to which it is invalid or unenforceable shall not be affected thereby, and each of the provisions of this Lease shall be valid and enforceable, unless enforcement of this Lease as so invalidated would be unreasonable or grossly inequitable under all the circumstances or would materially frustrate the purposes of this Lease.

21.5 Litigation Between Parties. In the event of any litigation or other dispute resolution proceedings between the parties hereto arising out of or in connection with this Lease, the prevailing party shall be reimbursed for all reasonable costs, including, but not limited to, reasonable accountants’ fees and attorneys’ fees, incurred in connection with such proceedings (including, but not limited to, any appellate proceedings relating thereto) or in connection with the enforcement of any judgment or award rendered in such proceedings. “Prevailing party” within the meaning of this Section shall include, without limitation, a party who dismisses an action for recovery hereunder in exchange for payment of the sums allegedly due, performance of covenants allegedly breached or consideration substantially equal to the relief sought in the action.

21.6 Surrender. A voluntary or other surrender of this Lease by Tenant, or a mutual termination thereof between Landlord and Tenant, shall not result in a merger but shall, at the option of Landlord, operate either as an assignment to Landlord of any and all existing subleases and subtenancies, or a termination of all or any existing subleases and subtenancies. This provision shall be contained in any and all assignments or subleases made pursuant to this Lease.

21.7 Interpretation. The provisions of this Lease shall be construed as a whole, according to their common meaning, and not strictly for or against Landlord or Tenant. The captions preceding the text of each Section and subsection hereof are included only for convenience of reference and shall be disregarded in the construction or interpretation of this Lease.

21.8 Entire Agreement. This written Lease, together with the exhibits hereto, contains all the representations and the entire understanding between the parties hereto with respect to the subject matter hereof. Any prior correspondence, memoranda or agreements are replaced in total by this Lease and the exhibits hereto. This Lease may be modified only by an agreement in writing signed by each of the parties.

21.9 Governing Law. This Lease and all exhibits hereto shall be construed and interpreted in accordance with and be governed by all the provisions of the laws of the State of California.

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21.10 No Partnership. The relationship between Landlord and Tenant is solely that of a lessor and lessee. Nothing contained in this Lease shall be construed as creating any type or manner of partnership, joint venture or joint enterprise with or between Landlord and Tenant.

21.11 Financial Information. From time to time Tenant shall promptly provide directly to prospective lenders and purchasers of the Property and/or Center designated by Landlord such financial information pertaining to the financial status of Tenant as Landlord may reasonably request; provided, Tenant shall be permitted to provide such financial information in a manner which Tenant deems reasonably necessary to protect the confidentiality of such information. In addition, from time to time, Tenant shall provide Landlord with such financial information pertaining to the financial status of Tenant as Landlord may reasonably request. Landlord agrees that all financial information supplied to Landlord by Tenant shall be treated as confidential material, and shall not be disseminated to any party or entity (including any entity affiliated with Landlord) without Tenant’s prior written consent, except that Landlord shall be entitled to provide such information, subject to reasonable precautions to protect the confidential nature thereof, (i) to Landlord’s partners and professional advisors, solely to use in connection with Landlord’s execution and enforcement of this Lease, and (ii) to prospective lenders and/or purchasers of the Property and/or Center, solely for use in connection with their bona fide consideration of a proposed financing or purchase of the Property and/or Center. For purposes of this Section, without limiting the generality of the obligations provided herein, it shall be deemed reasonable for Landlord to request copies of Tenant’s most recent audited annual financial statements, or, if audited statements have not been prepared, unaudited financial statements for Tenant’s most recent fiscal year, accompanied by a certificate of Tenant’s chief financial officer that such financial statements fairly present Tenant’s financial condition as of the date(s) indicated. Notwithstanding any other provisions of this Section 21.11, during any period in which Tenant has outstanding a class of publicly traded securities and is filing with the Securities and Exchange Commission, on a regular basis, Forms 10Q and 10K and any other periodic filings required under the Securities Exchange Act of 1934, as amended, it shall constitute sufficient compliance under this Section 21.11 for Tenant to furnish Landlord with copies of such periodic filings substantially concurrently with the filing thereof with the Securities and Exchange Commission.

Landlord and Tenant recognize the need of Tenant to maintain the confidentiality of information regarding its financial status and the need of Landlord to be informed of, and to provide to prospective lenders and purchasers of the Property and/or Center financial information pertaining to, Tenant’s financial status. Landlord and Tenant agree to cooperate with each other in achieving these needs within the context of the obligations set forth in this Section. Landlord also acknowledges and agrees that Tenant’s obligations to furnish information to Landlord under this Section are in all events subject to Tenant’s compliance with, and may therefore be limited by, applicable securities laws.

21.12 Costs. If Tenant requests the consent of Landlord under any provision of this Lease for any act that Tenant proposes to do hereunder, including, without limitation, assignment of this Lease or subletting of any one or more of the Buildings or any part thereof, Tenant shall, as a condition to doing any such act and the receipt of such consent, reimburse Landlord promptly for any and all reasonable costs and expenses incurred by Landlord in connection therewith, including, without limitation, reasonable attorneys’ fees.

21.13 Time. Time is of the essence of this Lease, and of every term and condition hereof.

21.14 Rules And Regulations. Tenant shall observe, comply with and obey, and shall cause its employees, agents and, to the best of Tenant’s ability, invitees to observe, comply with and obey such rules and regulations as Landlord may promulgate from time to time for the safety, care, cleanliness, order and use of the Improvements, the Property and the Center.

21.15 Brokers. Landlord agrees to pay a brokerage commission to CRESA Partners (“Tenant’s Broker”), in connection with the consummation of this Lease in the amount of $6.50 per rentable square foot, payable 50% upon mutual execution of this Lease and 50%, as to each Building, upon the Rent Commencement Date for such Building or, in the case of the Phase II Building, upon the Rent Commencement Date for each phase of the Phase II Building (in proportion to the ratio between the square footage covered by such phase and the total square footage of the Phase II Building). In addition, in the event Tenant exercises the Expansion

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Option, Landlord shall pay to Tenant’s Broker a commission on the same terms as set forth in the first sentence of this Section 21.15. Tenant shall be solely responsible for any claims for brokerage commissions or similar compensation by Tenant’s Broker and/or Mark Pearson in excess of the amount described in the preceding two sentences. Each party represents and warrants that no other broker participated in the consummation of this Lease and agrees to indemnify, defend and hold the other party harmless against any liability, cost or expense, including, without limitation, reasonable attorneys’ fees, arising out of any claims for brokerage commissions or other similar compensation in connection with any conversations, prior negotiations or other dealings by the indemnifying party with any other broker.

21.16 Memorandum Of Lease. At any time during the term of this Lease, either party, at its sole expense, shall be entitled to record a memorandum of this Lease and, if either party so elects, both parties agree to cooperate in the preparation, execution, acknowledgement and recordation of such document in reasonable form.

21.17 Corporate Authority. The person signing this Lease on behalf of Tenant warrants that he or she is fully authorized to do so and, by so doing, to bind Tenant.

21.18 Execution and Delivery. This Lease may be executed in one or more counterparts and by separate parties on separate counterparts, but each such counterpart shall constitute an original and all such counterparts together shall constitute one and the same instrument.

21.19 Survival. Without limiting survival provisions which would otherwise be implied or construed under applicable law, the provisions of Sections 2.5, 9.4, 11.2, 11.3, 11.4, 13.6, 14.6, 21.5 and 21.20 hereof shall survive the termination of this Lease with respect to matters occurring prior to the expiration of this Lease.

21.20 Parking and Traffic.

(a) Landlord has advised Tenant that the approval of the Britannia Oyster Point project by the City of South San Francisco was conditioned upon, among other things, Landlord’s development and implementation of a Transportation Demand Management Plan (the “TDMP”) pursuant to which Landlord is required to undertake various measures to try to reduce the volume of traffic generated by the Center. Landlord covenants with Tenant that Landlord will use reasonable efforts to try to reduce the volume of traffic generated by the Center, as contemplated by the TDMP, including (but not limited to) substantially complying with any specific measures required by the City of South San Francisco or its Redevelopment Agency. Tenant hereby agrees (i) to designate one of its employees to act as a liaison with Landlord’s designated transportation coordinator in facilitating and coordinating such programs as may be required from time to time by governmental agencies and/or by the terms of the TDMP to reduce the traffic generated by the Center (as required by the City of South San Francisco as part of the conditions of approval of this project) and to facilitate and encourage the use of public transportation, (ii) to make reasonable efforts to encourage cooperation and participation by Tenant’s employees in the programs implemented from time to time pursuant to the TDMP, including (but not limited to) programs described in this Section 21.20, and (iii) to cooperate with Landlord’s designated transportation coordinator in identifying an appropriate area within each Building where an information kiosk can be maintained for the dissemination of transportation-related information, to be updated from time to time by Landlord’s designated transportation coordinator.

(b) The Center is presently intended to contain a maximum of approximately 2.9 parking spaces per 1,000 square feet of rentable area in the buildings to be constructed on the Property, subject to approval by appropriate agencies of the City of South San Francisco. Consistent with the TDMP, a specified percentage (presently anticipated to be ten percent (10%)) of these spaces will be designated for carpool, vanpool and clean fuel vehicles. Among other things, the City of South San Francisco requires that Landlord charge a monthly parking fee for each parking space allocated to tenants and their employees. The monthly fee per parking space shall be [REDACTED] per parking space for each Building for the first five (5) years after the Rent Commencement Date for such Building, and shall increase to [REDACTED] per parking space for each Building immediately after the fifth (5^th) anniversary of the Rent Commencement Date for such Building. In accordance with the policies and requirements of the City of South San Francisco, Landlord recommends that Tenant pass through these parking charges to Tenant’s employees using the spaces. (Thus, for example, in years one (1) through five (5) of the Lease term, assuming an aggregate of 280,200 square feet in the Buildings and 2.9 spaces of parking per 1,000 square feet in the Center, Tenant would have 813 allocable parking spaces at [REDACTED] per space per month, for a total monthly parking fee of. [REDACTED]

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(c) On or about the date Tenant commences business in the respective Buildings, Landlord intends to provide Tenant,, through Landlord’s designated transportation coordinator, with an appropriate number of packets of employee transportation information, presently expected to include (but not be limited to) information about carpool parking; schedules and maps for SamTrans, Caltrain, BART and shuttle services operating to and from the Property; and a bicycle map. Landlord shall thereafter cause its designated transportation coordinator to provide updated copies of the employee transportation information packet to Tenant from time to time, as appropriate, and to make additional copies of the packet available to Tenant from time to time, upon request by Tenant, for new employees. Tenant shall distribute copies of the employee transportation information packet to all employees commuting to the Property at the time Tenant commences business in the respective Buildings, shall thereafter distribute copies of the packet to new employees from time to time and shall distribute updated packets to all employees from time to time when and as such updated packets are furnished to Tenant by Landlord’s designated transportation coordinator.

(d) Landlord is required to conduct, pursuant to the TDMP, annual surveys of its tenants and their employees regarding both quantitative and qualitative aspects of commuting and transportation patterns at the Center. Landlord anticipates that these surveys will be prepared, administered and analyzed by an independent transportation consultant retained by the City of South San Francisco, and will be summarized by that consultant in an annual report to be submitted by that consultant to the City of South San Francisco and its Redevelopment Agency with respect to the Center. Tenant shall cooperate with Landlord, with Landlord’s designated transportation coordinator and with any independent transportation consultant retained by the City, and shall use reasonable efforts to cause Tenant’s employees to so cooperate, in the completion and return of such surveys from time to time, when and as requested by Landlord or its designated transportation coordinator or the independent consultant. Tenant acknowledges and understands that employees who fail to respond to such surveys will be counted as drive-alone commuters.

(e) Landlord has advised Tenant that pursuant to conditions imposed by the City of South San Francisco and its Redevelopment Agency, Landlord may incur financial penalties if implementation of the TDMP at the Center fails to achieve a target rate of at least thirty-five percent (35%) alternative mode transportation usage (the “Alternative Mode Standard”) by employees working at the Center, as reflected in the surveys conducted pursuant to Section 21.20(d) above. Any such financial penalties shall be imposed by the City of South San Francisco Redevelopment Agency (the “Redevelopment Agency”), in its sole discretion, based on its review of the annual reports submitted from time to time pursuant to Section 21.20(d) above. The amount of such financial penalties is presently set at $15,000 per year for each percentage point (if any) by which, after a phase-in period (two (2) years after the granting of a certificate of occupancy) for each building, the aggregate rate of alternative mode transportation usage by employees throughout the Center falls short of the Alternative Mode Standard. If any such financial penalties are imposed on Landlord for failure to meet the Alternative Mode Standard on a Center-wide basis for any applicable survey period, then Landlord shall be entitled to pass such financial penalties through to all tenants of the Center whose employees have failed to demonstrate (pursuant to the applicable surveys) compliance with the Alternative Mode Standard for the applicable period (each such tenant being hereinafter referred to as a “Noncomplying Tenant” for that period), in which event the actual penalty amount shall be allocated among the Noncomplying Tenants for the applicable period in the following manner: Each Noncomplying Tenant shall bear a portion of the applicable penalty amount equal to a fraction, the numerator of which is the number of employees by which such Noncomplying Tenant fell short of meeting the Alternative Mode Standard for the applicable period and the denominator of which is the sum of the respective numbers of employees by which all Noncomplying Tenants, in the aggregate, fell short of meeting the Alternative Mode Standard for the applicable period. Each such Noncomplying Tenant shall pay its share of the applicable penalty amount to Landlord within thirty (30) days after receipt of written demand from Landlord, accompanied by supporting documentation evidencing the applicable penalty amount, as provided by the Redevelopment Agency or its consultant, and demonstrating in reasonable detail the calculation of such Noncomplying Tenant’s share of that penalty amount. Under no circumstances shall Tenant be required to bear any portion of any penalties

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contemplated in this paragraph with respect to any period as to which Tenant can demonstrate that its employees, as evidenced by the applicable survey(s) for that period, met the Alternative Mode Standard. If Tenant subleases any portion(s) of any of the Buildings from time to time, then for purposes of this Section 21.20, as between Tenant and Landlord, Tenant shall be fully and solely responsible for compliance by its subtenant(s) and their employees with the requirements of this Section 21.20, and all surveys and reports submitted by Tenant to Landlord or its designated transportation coordinator or to the independent consultant pursuant to this Section 21.20 shall cover the entire Buildings (other than the retail space in the Phase III Building) and shall report figures for Tenant and its subtenant(s) on an aggregate basis. Nothing in the preceding sentence, however, shall preclude Tenant, as between itself and its subtenant(s), from allocating to such subtenant(s) in the applicable sublease agreement any compliance obligations and/or penalty reimbursement obligations under this Section 21.20(e), but no such allocation shall be binding on Landlord or require Landlord, its designated transportation

[rest of page intentionally left blank; signature page follows]

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coordinator or the independent consultant to deal directly with any such subtenant(s) regarding the matters addressed in this Section 21.20. If Tenant believes, reasonably and in good faith, that there are circumstances particular to the nature of Tenant’s business operations that would justify a mitigation of penalties and/or a modification of the implementation of the TDMP as applied to Tenant’s business, and requests in writing (with supporting information describing, in reasonable detail, the circumstances on which Tenant is relying) that Landlord present such mitigation or modification arguments to the Redevelopment Agency, then Landlord shall use reasonable and good faith efforts to present or cause its designated transportation coordinator to present such mitigation and/or modification arguments, but Tenant acknowledges and understands that any decision with respect to such mitigation and/or modification arguments will be in the sole discretion of the Redevelopment Agency and agrees that Landlord shall have no liability to Tenant if such mitigation and/or modification arguments are not accepted by the Redevelopment Agency.

IN WITNESS WHEREOF, the parties hereto have executed this Lease as of the day and year first set forth above.

“Landlord”								“Tenant”
SLOUGH BTC, LLC, a Delaware limited liability company								TULARIK INC., a Delaware corporation
By:		Slough Estates USA Inc., a						By:
		Delaware corporation, Its Manager						Its:		CEO
		By:						By:
		Its:		VP				Its:		EVP

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EXHIBIT A

REAL PROPERTY DESCRIPTION (CENTER)

All that certain real property in the City of South San Francisco, County of San Mateo, State of California, more particularly described as follows:

Parcels 2, 3, 5 and 6 as shown on the Bay West Cove Final Subdivision Map, Parcel Map No. 97-027, recorded January 22, 1998 in Book 70, at pages 33-40, File No. 98-008274, Official Records of San Mateo County, California.

EXHIBIT C

WORKLETTER

This Workletter (“Workletter”) constitutes part of the Build-to-Suit Lease dated as of December 20, 2001 (the “Lease”) between SLOUGH BTC, LLC, a Delaware limited liability company (“Landlord”), and TULARIK INC., a Delaware corporation (“Tenant”). The terms of this Workletter are incorporated in the Lease for all purposes.

1. Defined Terms. As used in this Workletter, the following capitalized terms have the following meanings:

(a) Approved Plans: Plans and specifications prepared by the applicable Architect for the respective Improvements and approved by Landlord and, to the extent applicable, Tenant in accordance with Paragraph 2 of this Workletter, subject to further modification from time to time to the extent provided in and in accordance with such Paragraph 2.

(b) Architect: Chamorro Design Group, or any other architect selected by Landlord in its sole discretion, with respect to the respective Building Shells, the Site Improvements and any other Improvements which Landlord is to design pursuant to this Workletter; any architect selected by Tenant with the written approval of Landlord (which shall not be unreasonably withheld or delayed) with respect to the Tenant Improvements and any other Improvements which Tenant is to design pursuant to the this Workletter.

(c) Building Shells: The shells of the respective Buildings, as more fully described in Schedule C-1 attached to this Workletter, including the shell of the Connector Bridge (as described in Section 1.1(a) of the Lease).

(d) Change Order Request: See definition in Paragraph 2(e)(ii) hereof.

(e) Cost of Improvement: See definition in Paragraph 2(c) hereof.

(f) Final Completion Certificate: See definition in Paragraph 3(b) hereof.

(g) Final Working Drawings: See definition in Paragraph 2(a) hereof.

(h) General Contractor: Hathaway Dinwiddie Construction Company, or any other general contractor selected by Landlord in its sole discretion, with respect to Landlord’s Work, The General Contractor with respect to Tenant’s Work shall be selected by Tenant, subject to Landlord’s approval (not to be unreasonably withheld or delayed), as contemplated in Paragraph 5(a) hereof.

(i) Improvements: The Building Shells, Site Improvements, Tenant Improvements and other improvements shown on the Approved Plans from time to time and to be constructed on the Property pursuant to the Lease and this Workletter.

(j) Landlord Delay: See definition in Paragraph 10 hereof.

(k) Landlord’s Work: The Building Shells and Site Improvements, and any other Improvements which Landlord is to construct or install pursuant to this Workletter (including, but not limited to, any Tenant Improvements identified in Schedule C-2 to this Workletter as being Landlord’s responsibility to construct) or by mutual agreement of Landlord and Tenant from time to time.

(l) Punch List Work: Minor corrections of construction or decoration details, and minor mechanical adjustments, that are required in order to cause any applicable portion of the Improvements as constructed to conform to the Approved Plans in all material respects and that do not materially interfere with Tenant’s use or occupancy of the applicable Building and the Property.

(m) Site Improvements: The parking areas, driveways, landscaping and other improvements to the Common Areas of the Property that are depicted on Exhibit B to the Lease (as the same may be modified by Landlord from time to time pursuant to the process of development and approval of the Approved Plans).

(n) Structural Completion Certificate: See definition in Paragraph 3(a) hereof.

(o) Tenant Delay: Any of the following types of delay in the completion of construction of the Building Shell(s):

(i) Any delay resulting from Tenant’s failure to furnish, within the time frames required in the Estimated Construction Schedules attached as Exhibit D to the Lease (or, in the case of any requests for which no specific time frame is specified in such Estimated Construction Schedules, within the time frame reasonably specified in writing by Landlord or its project manager in making such request), information reasonably requested by Landlord or by Landlord’s project manager (Project Management Advisors, Inc. or such other person or entity as Landlord may designate from time to time) in connection with the design or construction of the respective Building Shells, or from Tenant’s failure to approve within the time frames required in the Estimated Construction Schedules attached as Exhibit D to the Lease (or, in the case of any requests for which no specific time frame is specified in such Estimated Construction Schedules, within the time frame reasonably specified in writing by Landlord or its project manager in requesting such approval) any matters requiring approval by Tenant;

(ii) Any delay resulting from changes in Landlord’s Final Working Drawings and/or Landlord’s Approved Plans with respect to the Phase IA Building and/or the Phase IB Building in order to accommodate the construction of the Connector Bridge, under the circumstances and to the extent provided in Paragraph 2(e)(iii) of this Workletter;

(iii) Any delay resulting from Change Order Requests initiated by Tenant, including any delay resulting from the need to revise any drawings or obtain further governmental approvals as a result of any such Change Order Request; or

(iv) Any delay of any other kind or nature caused by Tenant (or Tenant’s contractors, agents or employees) or resulting from the performance of Tenant’s Work.

(p) Tenant Improvements: The improvements to or within the respective Buildings, other than improvements constituting part of the respective Building Shells, shown on the Approved Plans from time to time and to be constructed by Tenant (except as otherwise provided herein) pursuant to the Lease and this Workletter, including (but not limited to) the improvements described in Schedule C-2 attached to this Workletter.

(q) Tenant’s Work: All of the Improvements other than those constituting Landlord’s Work, and such other materials and improvements as Tenant deems necessary or appropriate for Tenant’s use and occupancy of the respective Buildings.

(r) Unavoidable Delays: Delays due to acts of God, action or inaction of public agencies, labor disputes, strikes, fires, freight embargoes, rainy or stormy weather (but only to the extent such weather prevents the affected party from conducting any substantial element of its construction work for a period of at least one full work day), inability to obtain supplies, materials, fuels or permits, delays of contractors or subcontractors, or other causes or contingencies beyond the reasonable control of Landlord or Tenant, as applicable.

(s) Work Deadlines: The target dates for performance by the applicable party of the steps listed in the Estimated Construction Schedules for the respective Buildings attached as Exhibit D to the Lease.

(t) Capitalized terms not otherwise defined in this Workletter shall have the definitions set forth in the Lease.

2. Plans, Cost of Improvements and Construction. Landlord and Tenant shall comply with the procedures set forth in this Paragraph 2 in preparing, delivering and approving matters relating to the Improvements.

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(a) Approved Plans and Working Drawings for Landlord’s Work. Landlord shall promptly and diligently (and in all events prior to any applicable Work Deadlines, subject to Tenant Delays and Unavoidable Delays) prepare or cause to be prepared plans and specifications for the Improvements constituting Landlord’s Work and for all other Improvements (if any) for which Landlord is expressly assigned design responsibility under Schedule C-2 to this Workletter. Such plans and specifications shall not be subject to Tenant’s approval, except to the extent (and only to the extent) that Landlord’s Work includes, pursuant to this Workletter or by other mutual agreement of Landlord and Tenant, any portion of the Tenant Improvements. Landlord shall deliver copies of such plans and specifications to Tenant for Tenant’s approval (but only to the extent provided in the preceding sentence) and information, to assist Tenant in providing any information and making any decisions necessary to be provided or made by Tenant in order to permit preparation of Landlord’s Final Working Drawings as hereinafter defined, and to assist Tenant in preparing plans, specifications and drawings for Tenant’s Work as hereinafter set forth. Following approval of such plans and specifications by Landlord and, if applicable, by Tenant (as so approved, the “Landlord’s Approved Plans”), Landlord shall then prepare or cause to be prepared, on or before the applicable Work Deadline (assuming timely delivery by Tenant of all information and decisions required to be furnished or made by Tenant in order to permit complete preparation of Landlord’s Final Working Drawings), final detailed working drawings and specifications for the Improvements constituting Landlord’s Work, including structural, fire protection, life safety, mechanical and electrical working drawings and final architectural drawings (collectively, “Landlord’s Final Working Drawings’’). Landlord’s Final Working Drawings shall substantially conform to the Landlord’s Approved Plans. Landlord’s Final Working Drawings shall not be subject to Tenant’s approval, except to the extent (and only to the extent), as noted above, that Landlord’s Work includes, pursuant to this Workletter or by other mutual agreement of Landlord and Tenant, any portion of the Tenant Improvements. Landlord shall deliver copies of Landlord’s Final Working Drawings to Tenant for Tenant’s approval (but only to the extent provided in the preceding sentence) and information, and to assist Tenant in preparing plans, specifications and drawings for Tenant’s Work as hereinafter set forth. Landlord’s obligation to deliver Landlord’s Final Working Drawings to Tenant within the time period set forth above shall be extended for any delay encountered by Landlord as a result of a request by Tenant for changes in accordance with the procedure set forth below, any other Tenant Delays, or any Unavoidable Delays. To the extent Tenant has any right of approval over Landlord’s proposed plans and specifications or Landlord’s proposed Final Working Drawings pursuant to the foregoing provisions, no later than the applicable Work Deadline (assuming timely delivery of plans and drawings by Landlord), Tenant shall either approve (to the extent of Tenant’s approval right) Landlord’s proposed plans and specifications or Landlord’s proposed Final Working Drawings, as applicable, or set forth in writing with particularity any changes necessary to bring the aspects of such proposed plans and specifications or proposed Landlord’s Final Working Drawings over which Tenant has a right of approval into a form which will be acceptable to Tenant or, in the case of Landlord’s Final Working Drawings, into substantial conformity with the Landlord’s Approved Plans. Notwithstanding any other provisions of this paragraph (other than the final sentence thereof), in no event shall Tenant have the right to object to any aspect of the Landlord’s proposed plans and specifications or proposed Landlord’s Final Working Drawings (including, but not limited to, any subsequently proposed changes therein from time to time) that is necessitated by applicable law or as a condition of any governmental or other third-party approvals that are required to be obtained in connection with Landlord’s Work, or that is required as a result of unanticipated conditions encountered in the course of construction of Landlord’s Work. Failure of Tenant to deliver to Landlord written notice of disapproval and specification of required changes (to the extent Tenant has a right of approval or objection under this paragraph) on or before the applicable Work Deadline shall constitute and be deemed to be approval of Landlord’s proposed plans and specifications or proposed Landlord’s Final Working Drawings, as applicable. Upon approval, actual or deemed, of Landlord’s Final Working Drawings by Landlord and Tenant (to the extent Tenant has such a right of approval under this paragraph), Landlord’s Final Working Drawings shall be deemed to be incorporated in and considered part of the Landlord’s Approved Plans, superseding (to the extent of any inconsistencies) any inconsistent features of the previously existing Landlord’s Approved Plans, Notwithstanding the foregoing provisions of this paragraph, the parties acknowledge and agree as follows: (i) as to the Building Shells for the Phase IA and Phase IB Buildings (excluding the Connector Bridge, which has not yet been designed), the plans and specifications for which building permits have already been issued by the City of South San Francisco constitute Landlord’s Approved Plans for such Building Shells, subject to any changes that may be required in connection with the design and construction of the Connector Bridge; (ii) as to the Building Shell for the Phase II Building, the plans and specifications filed with Landlord’s pending permit application with the City of South San Francisco constitute Landlord’s Approved Plans for such Building Shell, subject to any changes

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that may be required by the City of South San Francisco in connection with the issuance of a building permit for such Building Shell; and (iii) Tenant shall have a right of approval over the plans and specifications to be prepared by Landlord for the shell of the Connector Bridge which approval shall not be unreasonably withheld and which right of approval shall be exercised within any applicable Work Deadlines or, to the extent there is no specifically applicable Work Deadline, within five (5) business days after delivery of plans and specifications for review by Tenant.

(b) Approved Plans and Working Drawings for Tenant’s Work. Tenant shall promptly and diligently cause to be prepared and delivered to Landlord, for approval, a space plan and detailed plans and specifications for the Improvements constituting Tenant’s Work (as so approved, the “Tenant’s Approved Plans”). Landlord shall approve or disapprove of Tenant’s Plans, following receipt thereof from Tenant, within the applicable number of days specified on the applicable Estimated Construction Schedule(s) attached as Exhibit D to the Lease. Following mutual approval of the Tenant’s Approved Plans, Tenant shall then cause to be prepared and delivered to Landlord, for approval, final working drawings and specifications for the Improvements constituting Tenant’s Work, including any applicable life safety, mechanical and electrical working drawings and final architectural drawings (collectively, “Tenant’s Final Working Drawings”). Tenant’s Final Working Drawings shall substantially conform to the Tenant’s Approved Plans. Landlord shall, within the applicable number of days specified on the applicable Estimated Construction Schedule(s) attached as Exhibit D to the Lease, either approve Tenant’s Final Working Drawings or set forth in writing with particularity any changes necessary to bring Tenant’s Final Working Drawings into substantial conformity with Tenant’s Approved Plans or into a form which will be acceptable to Landlord. Upon approval of Tenant’s Final Working Drawings by Landlord and Tenant, Tenant’s Final Working Drawings shall be deemed to be incorporated in and considered part of the Tenant’s Approved Plans, superseding (to the extent of any inconsistencies) any inconsistent features of the previously existing Tenant’s Approved Plans.

(c) Cost of Improvements. “Cost of Improvement” shall mean, with respect to any item or component for which a cost must be determined in order to allocate such cost, or an increase in such cost, to Landlord and/or Tenant pursuant to this Workletter, the sum of the following (unless otherwise agreed in writing by Landlord and Tenant with respect to any specific item or component or any category of items or components): (i) all sums paid to contractors or subcontractors for labor and materials furnished in connection with construction of such item or component; (ii) all costs, expenses, payments, fees and charges (other than penalties) paid or incurred to or at the direction of any city, county or other governmental or quasi-governmental authority or agency which are required to be paid in order to obtain all necessary governmental permits, licenses, inspections and approvals relating to construction of such item or component; (iii) engineering and architectural fees for services rendered in connection with the design and construction of such item or component (including, but not limited to, the applicable Architect for such item or component and an electrical engineer, mechanical engineer and civil engineer); (iv) sales and use taxes; (v) testing and inspection costs; (vi) the cost of power, water and other utility facilities and the cost of collection and removal of debris required in connection with construction of such item or component; (vii) all other “hard” costs incurred in the construction of such item or component in accordance with the applicable Approved Plans and this Workletter; and (viii)as to the Tenant Improvements, all costs and items specifically described as being at Tenant’s cost in Schedules C-l and C-2 attached hereto. Notwithstanding the foregoing provisions, however, Cost of Improvement shall not include any project management fee relating to the construction of the applicable item or component, except to the extent of any project management fees expressly set forth in Schedules C-l and C-2 attached hereto.

(d) Construction of Landlord’s Work. Promptly following approval of Landlord’s Final Working Drawings, Landlord shall apply for and use reasonable efforts to obtain the necessary permits and approvals to allow construction of all Improvements constituting Landlord’s Work. Upon receipt of such permits and approvals, Landlord shall, at Landlord’s sole expense (except as otherwise provided in the Lease or in this Workletter), diligently construct and complete the Improvements constituting Landlord’s Work substantially in accordance with the Landlord’s Approved Plans, subject to Unavoidable Delays and Tenant Delays (if any). Such construction shall be performed in a neat and workmanlike manner and shall conform to all applicable governmental codes, laws and regulations in force at the time such work is completed. Without limiting the generality of the foregoing, Landlord shall be

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responsible for compliance of all Improvements designed and constructed by Landlord with the requirements of the Americans with Disabilities Act and all similar or related requirements pertaining to access by persons with disabilities. Landlord shall have the right, in its sole discretion, to decide whether and to what extent to use union labor on or in connection with Landlord’s Work and shall use the General Contractor designated or selected pursuant to Paragraph 1(h) to construct all Improvements constituting Landlord’s Work.

(e) Changes.

(i) If Landlord determines at any time that changes in Landlord’s Final Working Drawings or in any other aspect of the Landlord’s Approved Plans relating to any item of Landlord’s Work are required as a result of applicable law or governmental requirements, or at the insistence of any other third party whose approval may be required with respect to the Improvements, or are required as a result of unanticipated conditions encountered in the course of construction, then Landlord shall promptly (A) advise Tenant of such circumstances and (B) cause revised Landlord’s Approved Plans and/or Landlord’s Final Working Drawings, as applicable, reflecting such changes to be prepared by Architect and submitted to Tenant, for Tenant’s information (and to assist Tenant in determining the need for any related changes in Tenant’s Approved Plans) and, to the extent such changes relate to any Tenant Improvements being constructed by Landlord pursuant to mutual agreement of Landlord and Tenant or are subject to Tenant’s approval pursuant to the final sentence of this paragraph, for approval by Tenant in accordance with the procedure contemplated in Paragraph 2(a) hereof. Upon final approval of such revised drawings by Landlord and Tenant (if applicable), Landlord’s Final Working Drawings and/or the Landlord’s Approved Plans shall be deemed to be modified accordingly. In the case of any such changes in Landlord’s Final Working Drawings and/or Landlord’s Approved Plans that are required as a result of applicable law or governmental requirements, or are required at the insistence of any other third party whose approval is required with respect to the Improvements, or are required as a result of unanticipated conditions encountered in the course of construction, Tenant shall have no approval right and Landlord shall have no liability or responsibility for any costs or cost increases incurred by Tenant as a result of any such required changes. However, in the case of any changes in Landlord’s Final Working Drawings and/or Landlord’s Approved Plans that are merely deemed desirable by Landlord without being required by any of the circumstances described in the preceding sentence, (A) Landlord shall not make any such change without Tenant’s written approval, which approval shall not be unreasonably withheld and which right of approval shall be exercised within five (5) business days after Tenant’s receipt of Landlord’s request for approval of the proposed change, and (B) Landlord shall be responsible for all actual costs or cost increases reasonably incurred by Tenant as a result of such changes and shall reimburse Tenant for any such actual costs or cost increases promptly following receipt of Tenant’s written request for such reimbursement, accompanied by documentation reasonably supporting Tenant’s claimed costs or cost increases and their relationship to the changes made by Landlord.

(ii) If Tenant at any time desires any changes, alterations or additions to the Landlord’s Approved Plans or Landlord’s Final Working Drawings with respect to any of Landlord’s Work, Tenant shall submit a detailed written request to Landlord specifying such changes, alterations or additions (a “Change Order Request”). Upon receipt of any such request, Landlord shall promptly notify Tenant of (A) whether the matters proposed in the Change Order Request are approved by Landlord (which approval shall not be unreasonably withheld as to any matters relating to Tenant Improvements which are being constructed by Landlord pursuant to mutual agreement of Landlord and Tenant, but may be granted or withheld by Landlord in its sole discretion as to any other aspects of Landlord’s Work), (B) Landlord’s estimate of the number of days of delay, if any, which shall be caused by such Change Order Request if implemented (including, without limitation, delays due to the need to obtain any revised plans or drawings and any governmental approvals), and (C) Landlord’s estimate of the increase, if any, which shall occur in the Cost of Improvement for the items or components affected by such Change Order Request if such Change Order Request is implemented (including, but not limited to, any costs of compliance with laws or governmental regulations that become applicable because of the implementation of the Change Order Request). If Landlord approves the Change Order Request and Tenant notifies Landlord in writing, within five (5) business days after receipt of such notice from Landlord, of Tenant’s approval of the Change Order Request (including the estimated delays and cost increases, if any, described in Landlord’s notice), then Landlord shall cause such Change Order Request to be implemented and Tenant shall be responsible for all costs or cost increases resulting from or attributable to the implementation of the Change Order Request, subject to the provisions of Paragraph 4 hereof. If Tenant fails to notify Landlord in writing of Tenant’s approval of such Change Order Request within said five (5) business day period, then such Change Order Request shall be deemed to be withdrawn and shall be of no further effect.

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(iii) If Landlord determines at any time in the course of design and construction of the Connector Bridge that changes in Landlord’s Final Working Drawings or in any other aspect of the Landlord’s Approved Plans for the Phase IA Building and/or the Phase IB Building are required in order to accommodate the construction of the Connector Bridge, then Landlord shall promptly (A) advise Tenant of such circumstances and (B) notify Tenant of Landlord’s estimate of the number of days of delay, if any, which shall be caused in Landlord’s achievement of structural completion for the Phase IA Building and/or the Phase IB Building as a result of such changes if implemented (including, without limitation, delays due to the need to obtain any revised plans or drawings and any governmental approvals) (the “Estimated Delay”). If Tenant notifies Landlord in writing, within five (5) business days after receipt of such notice from Landlord, of Tenant’s approval of the Connector Bridge design which requires such changes and of Tenant’s desire to have Landlord proceed with the construction of the Connector Bridge notwithstanding the Estimated Delay (if any), then Landlord shall cause such changes to be implemented and the amount of the Estimated Delay (if any) as specified in Landlord’s notice shall constitute a Tenant Delay; provided, however, that notwithstanding the characterization of such changes as a Tenant Delay and notwithstanding any contrary provisions of the Lease or of this Workletter, under no circumstances shall Tenant be responsible for any costs or cost increases resulting from or attributable to the implementation of the changes described in this subparagraph (iii). If Tenant fails to notify Landlord in writing, within said five (5) business day period, of Tenant’s approval of the Connector Bridge design which requires such changes and of Tenant’s desire to have Landlord proceed with the construction of the Connector Bridge notwithstanding the estimated delays (if any), then such design changes shall be deemed to be disapproved and Landlord shall be under no further obligation to construct the Connector Bridge.

(iv) If Tenant at any time desires to make any changes, alterations or additions to the Tenant’s Approved Plans, such changes, alterations or additions shall be subject to approval by Landlord in the same manner as the original Tenant’s Approved Plans as provided above.

(a) When Landlord receives written certification from Architect that construction of the foundation, structural slab on grade (except to the extent delayed at Tenant’s request to accommodate Tenant’s design requirements and/or any underslab aspects of Tenant’s Work), Landlord’s underslab plumbing work, structural steel framework, decking and concrete on second, third and fourth (if applicable) floors, roof structure, roof membrane and installation of main fire sprinkler risers in a Building have been substantially completed in accordance with the Landlord’s Approved Plans, Landlord shall prepare and deliver to Tenant a certificate signed by both Landlord and Architect (the “Structural Completion Certificate”) certifying that the construction of such portions of the applicable Building has been substantially completed in accordance with the Landlord’s Approved Plans in all material respects and specifying the date of that completion. The delivery of such Structural Completion Certificate shall commence the running of the 180-day time period (which period shall be extended day for day by any Landlord Delay, as hereinafter defined, occurring after the date of delivery of such Structural Completion Certificate) until the Rent Commencement Date for the applicable Building (or in the case of the Phase II Building, until the Phase IIA Rent Commencement Date) under Section 2.1 of the Lease. Notwithstanding any other provisions of this Workletter or of the Lease, Landlord’s right to issue a Structural Completion Certificate with respect to the respective Phase I Buildings shall be determined without reference to the degree of completion of the Connector Bridge, and any delay in the construction or structural completion of the shell for the Connector Bridge shall not delay the determination of structural completion or the Rent Commencement Date for either of the Phase I Buildings, treating each of such Buildings (without the Connector Bridge) as a stand alone building and ignoring, for this purpose, any lack of completion of Landlord’s Work at and in the immediate vicinity of the point of attachment of the Connector Bridge to the applicable Building.

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(b) When Landlord receives written certification from Architect that construction of the remaining Improvements constituting Landlord’s Work with respect to a Building has been substantially completed in accordance with the Landlord’s Approved Plans (except for Punch List Work), Landlord shall prepare and deliver to Tenant a certificate signed by both Landlord and Architect (the “Final Completion Certificate”) certifying that the construction of the remaining Improvements constituting Landlord’s Work with respect to such Building has been substantially completed in accordance with the Landlord’s Approved Plans in all material respects, subject only to completion of Punch List Work, and specifying the date of that completion. Upon receipt by Tenant of the Final Completion Certificate, the Improvements constituting Landlord’s Work will be deemed delivered to Tenant for all purposes of the Lease (subject to Landlord’s continuing obligations with respect to the Punch List Work). Notwithstanding any other provisions of this Workletter or of the Lease, Landlord’s right to issue a Final Completion Certificate with respect to the respective Phase I Buildings shall be determined without reference to the degree of completion of the Connector Bridge, and any delay in the construction or final completion of the shell for the Connector Bridge shall not delay the determination of final completion or the Rent Commencement Date for either of the Phase I Buildings, treating each of such Buildings (without the Connector Bridge) as a stand-alone building and ignoring, for this purpose, any lack of completion of Landlord’s Work at and in the immediate vicinity of the point of attachment of the Connector Bridge to the applicable Building.

(c) Notwithstanding any other provisions of this Workletter or of the Lease, Rent Commencement Dates for the applicable Buildings shall be subject to adjustment under the following circumstances:

(i) If Landlord is delayed in substantially completing any of Landlord’s Work necessary for issuance of the Structural Completion Certificate with respect to a Building as a result of any Tenant Delay, then the 180-day period between the delivery of the Structural Completion Certificate and the Rent Commencement Date for such Building pursuant to Section 2.1 of the Lease shall be reduced, day for day, by the number of days by which such Tenant Delay delayed completion of the portions of Landlord’s Work necessary for issuance of the Structural Completion Certificate for such Building, and Tenant shall reimburse Landlord in cash, within fifteen (15) days after written demand by Landlord (accompanied by reasonable documentation of the items claimed), for any increased construction-related costs and expenses incurred by Landlord as a result of the Tenant Delay (except to the extent otherwise expressly provided in Paragraph 2(e)(iii) of this Workletter).

(ii) If Tenant is delayed in substantially completing any of Tenant’s Work necessary for Tenant’s occupancy of and commencement of business in a Building as a result of any Landlord Delay, then the 180-day period between the delivery of the Structural Completion Certificate and the Rent Commencement Date for such Building pursuant to Section 2.1 of the Lease shall be extended, day for day, by the number of days by which such Landlord Delay delayed completion of the portions of Tenant’s Work necessary for Tenant’s occupancy of and commencement of business in such Building.

(iii) Rent Commencement Dates shall also be subject to adjustment under the circumstances and to the extent provided in Section 2.1 (c) of the Lease, if applicable.

(d) At any time within thirty (30) days after delivery of the Structural Completion Certificate or the Final Completion Certificate, as applicable, for a Building, Tenant shall be entitled to submit one or more lists to Landlord specifying Punch List Work to be performed on the applicable Improvements constituting Landlord’s Work with respect to such Building, and upon receipt of such list(s), Landlord shall diligently complete such Punch List Work at Landlord’s sole expense. Promptly after Landlord provides Tenant with the Final Completion Certificate for a Building, Landlord shall cause the recordation of a Notice of Completion (as defined in Section 3093 of the California Civil Code) with respect to Landlord’s Work for such Building.

4. Payment of Costs.

(a) Landlord’s Work. Except as otherwise expressly provided in this Workletter (including, but not limited to, the cost allocations set forth in Schedules C-1 and C-2 attached hereto) or by mutual written agreement of Landlord and Tenant, the cost of construction of Landlord’s Work shall be borne by Landlord at its sole cost and expense, including any costs or cost increases incurred as a result of Unavoidable Delays, governmental requirements or unanticipated conditions; provided, however, that notwithstanding any other provisions of this

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Paragraph 4(a), to the extent the Cost of Improvement relating to the construction of any item or component of Landlord’s Work is increased as a result of any implemented Change Order Request or any Tenant Delay, or as a result of any other plan changes or compliance costs attributable to Tenant’s particular use requirements or to the contemplated Tenant’s Work, the amount of the increase in the Cost of Improvement with respect to such item or component, as well as the Cost of Improvement with respect to any matters listed on Schedule C-1 or C-2 as being installed by Landlord but as having the cost thereof borne by Tenant, shall be reimbursed by Tenant to Landlord in cash or, by mutual agreement of Landlord and Tenant, may be deducted from Landlord’s maximum obligation under Paragraph 4(b) with respect to the cost of Tenant’s Work.

(b) Tenant’s Work. Except as otherwise expressly provided in this Workletter (including, but not limited to, the cost allocations set forth in Schedules C-1 and C-2 attached hereto) or by mutual written agreement of Landlord and Tenant, the cost of construction of Tenant’s Work shall be borne by Tenant at its sole cost and expense, including any costs or cost increases incurred as a result of Unavoidable Delays, governmental requirements or unanticipated conditions. Notwithstanding the foregoing sentence, the Cost of Improvements with respect to the construction of the Tenant Improvements in each Building shall be borne by Landlord up to a maximum contribution by Landlord equal to [REDACTED] per square foot, in the case of each of the Phase I Buildings (including the connector Bridge), and [REDACTED] per square foot, in the case of each phase of the Phase II Building, times the square footage of the applicable Building, as and when constructed (measured in accordance with Sections 1.1(c) and 3.1(d) of the Lease), toward the Cost of Improvements for the Tenant Improvements in the respective Buildings (the “Tenant Improvement Allowance”), less any reduction in such sum pursuant to Paragraph 4(a) or any other applicable provision of this Workletter. Tenant shall be entitled to utilize the entire Tenant Improvement Allowance, for each respective Building or phase prior to being required to expend any of Tenant’s own funds on an unreimbursed basis for Tenant Improvements in such Building or phase. In all other respects, the timing, conditions and other procedures for Landlord’s disbursement of the Tenant Improvement Allowance for each Building or phase shall be as reasonably prescribed by Landlord, subject to approval by Tenant (which approval shall not be unreasonably withheld or delayed by Tenant); provided, however, that progress payments of the Tenant Improvement Allowance shall be made not less often than monthly, subject to Tenant’s timely compliance with ail applicable conditions and procedures established pursuant to this sentence. To the extent the Cost of Improvement with respect to the Tenant Improvements for any Building or Phase exceeds the Tenant Improvement Allowance (as reduced, if applicable), whether as a result of implemented Change Order Requests, Tenant Delays and/or Unavoidable Delays or otherwise, the amount of such excess shall in all events be Tenant’s sole responsibility and expense. The rental amounts set forth in Section 3.1 of the Lease are not subject to adjustment based on the Cost of Improvements of the Tenant Improvements, regardless of whether the final Cost of Improvements for the Tenant Improvements in any Building or Phase uses the entire Tenant Improvement Allowance or not. The foregoing Tenant Improvement Allowance assumes that each Phase I Building will be composed of a minimum of 65% laboratory space and a maximum of 35% office space, and that the Phase II Building will be composed of a minimum of 50% laboratory space and a maximum of 50% office space, and such Tenant Improvement Allowance shall be subject to reduction (and/or to disapproval by Landlord of Tenant’s proposed plans and specifications for the Tenant Improvements in the applicable Building) if the proposed laboratory space in a Building is less than the minimum percentage specified in this sentence. The square footage attributable to the Connector Bridge shall be disregarded for purposes of applying the ratios set forth in the preceding sentence to the Phase I Buildings.

(c) Tenant Funding of Tenant Improvement Allowance. If Landlord fails to timely fulfill its obligation to fund any portion of the Tenant Improvement Allowance pursuant to Paragraph 4(b) above, Tenant shall be entitled to deliver written notice thereof (a “Payment Notice”) to Landlord. If Landlord still fails to fulfill any such payment obligation within seventy-five (75) days after Landlord’s receipt of the Payment Notice from Tenant and fails to deliver written notice to Tenant within such 75-day period explaining the reasons for which Landlord believes that the amounts described in Tenant’s Payment Notice are not in fact due and payable by Landlord, then Tenant shall be entitled to fund the portion of the Tenant Improvement Allowance described in the Payment Notice and to offset the amount so funded, together with interest at the prime rate plus two percentage points (2%) from the date of funding until the date of offset, against Tenant’s next obligations to pay Rent under the Lease.

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5. Tenant’s Work. Tenant shall construct and install in each Building or Phase the Tenant’s Work, substantially in accordance with the Tenant’s Approved Plans or, with respect to Tenant’s Work not otherwise shown on the Tenant’s Approved Plans, substantially in accordance with plans and specifications prepared by Tenant and approved in writing by Landlord (which approval shall not be unreasonably withheld or delayed). Tenant’s Work shall be performed in accordance with, and shall in all respects be subject to, the terms and conditions of the Lease (to the extent not inconsistent with this Workletter), and shall also be subject to the following conditions:

(a) Contractor Requirements. The contractor engaged by Tenant for Tenant’s Work, and any subcontractors, shall be duly licensed in California and shall be subject to Landlord’s prior written approval, which approval shall not be unreasonably withheld or delayed. Tenant shall engage only union contractors for the construction of Tenant’s Work and for the installation of Tenant’s fixtures and equipment in the Buildings, and shall require all such contractors engaged by Tenant, and all of their subcontractors, to use only union labor on or in connection with such work, except to the extent Landlord determines, in its reasonable discretion, that the use of non-union labor would not create a material risk of labor disputes, picketing or work interruptions at the Property, in which event Landlord shall, to that extent, waive such union labor requirement.

(b) Costs and Expenses of Tenant’s Work. Subject to Landlord’s payment or reimbursement obligations under Paragraph 4(b) hereof with respect to the Tenant Improvement Allowance, Tenant shall promptly pay all costs and expenses arising out of the performance of Tenant’s Work (including the costs of permits) and shall furnish Landlord with evidence of payment on request. Tenant shall provide Landlord with ten (10) days’ prior written notice before commencing any Tenant’s Work. On completion of Tenant’s Work (assuming Landlord has complied with its payment or reimbursement obligations under Paragraph 4(b) hereof), Tenant shall deliver to Landlord a release and unconditional lien waiver executed by each contractor, subcontractor and materialman involved in the performance of Tenant’s Work, if any lien is filed against the Property or against Tenant’s leasehold interest, Tenant shall obtain, within ten (10) days after the filing, the release or discharge of that lien. If Tenant fails to do so, Landlord shall have the right (but not the obligation) to obtain the release or discharge of the lien and Tenant shall, within fifteen (15) days after written demand by Landlord (accompanied by reasonable documentation of the items claimed), reimburse Landlord for all costs, including (but not limited to) reasonable attorneys’ fees, incurred by Landlord in obtaining the release or discharge of such lien, together with interest from the date of demand at the interest rate set forth in Section 3.2 of the Lease.

(c) Indemnification. Tenant shall indemnify, defend (with counsel satisfactory to Landlord) and hold Landlord and its agents and employees harmless from all suits, claims, actions, losses, costs and expenses (including, but not limited to, claims for workers’ compensation, attorneys’ fees and costs) based on personal injury or property damage or contract claims (including, but not limited to, claims for breach of warranty) arising from the performance of Tenant’s Work, including (but not limited to) from any early access to the Property by Tenant and its contractors in preparation for Tenant’s Work as contemplated in Section 2.2 of the Lease and in this Workletter, Tenant shall repair or replace (or, at Landlord’s election, reimburse Landlord for the cost of repairing or replacing) any portion of the Improvements and/or any of Landlord’s real or personal property or equipment that is damaged, lost or destroyed in the course of or in connection with the performance of Tenant’s Work.

(d) Insurance. Tenant’s contractors shall obtain and provide to Landlord certificates evidencing workers’ compensation, public liability, and property damage insurance in amounts and forms and with companies reasonably satisfactory to Landlord.

(e) Rules and Regulations. Tenant and Tenant’s contractors shall comply with any other reasonable rules, regulations and requirements that Landlord or Landlord’s General Contractor or project manager may impose from time to time with respect to the performance of Tenant’s Work. Tenant’s agreement with Tenant’s contractors shall require each contractor to provide daily cleanup of the construction area to the extent that such cleanup is necessitated by the performance of Tenant’s Work.

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(f) Early Entry. Landlord shall permit entry of contractors into the Buildings for the purposes of performing Tenant’s Work, upon delivery of the Structural Completion Certificate and, to the extent provided in Section 2.2 of the Lease, prior to such delivery, subject to satisfaction of the conditions set forth in the Lease and in this Workletter. This license to enter is expressly conditioned on the contractor(s) retained by Tenant working in harmony with, and not interfering with, the workers, mechanics and contractors of Landlord. If at any time the entry or work by Tenant’s contractor(s) causes any material interference with the workers, mechanics or contractors of Landlord, permission to enter may be withdrawn by Landlord immediately on written notice to Tenant. Landlord agrees to use reasonable efforts to cause its workers, mechanics and contractors to work in harmony with Tenant’s contractors. Any unreasonable exclusion of Tenant’s contractors from the Buildings shall be a Landlord Delay to the extent provided in the definition of that term.

(g) Risk of Loss. All materials, work, installations and decorations of any nature brought onto or installed in the Buildings, by or at the direction of Tenant or in connection with the performance of Tenant’s Work, before the applicable Rent Commencement Date shall be at Tenant’s risk, and neither Landlord nor any party acting on Landlord’s behalf shall be responsible for any damage, loss or destruction thereof.

(h) Condition of Tenant’s Work. All work performed by Tenant shall be performed in a good and workmanlike manner, shall be free from defects in design, materials and workmanship, and shall be completed in compliance with the plans approved by Landlord for such Tenant’s Work in all material respects and in compliance with all applicable governmental laws, ordinances, codes and regulations in force at the time such work is completed. Without limiting the generality of the foregoing, Tenant shall be responsible for compliance of all Improvements designed and constructed by Tenant with the requirements of the Americans with Disabilities Act and all similar or related requirements pertaining to access by persons with disabilities.

6. [Omitted.]

7. No Agency. Nothing contained in this Workletter shall make or constitute Tenant as the agent of Landlord. .

8. Survival. Without limiting survival provisions which would otherwise be implied or construed under applicable law, the provisions of Paragraph 5(c) of this Workletter shall survive the termination of the Lease with respect to matters occurring prior to expiration of the Lease.

9. Miscellaneous. All references in this Workletter to a number of days shall be construed to refer to calendar days, unless otherwise specified herein. In all instances where Tenant’s approval is required, if no written notice of disapproval is given within the applicable time period, at the end of that period Tenant shall be deemed to have given approval (unless the provision requiring Tenant’s approval expressly states that non-response is deemed to be a disapproval or withdrawal of the pending action or request, in which event such express statement shall be controlling over the general statement set forth in this sentence) and the next succeeding time period shall commence. If any item requiring approval is disapproved by Tenant in a timely manner, the procedure for preparation of that item and approval shall be repeated.

10. Landlord Delay. As used in this Workletter and the Lease, “Landlord Delay” shall mean any of the following types of delay in the completion of construction of the Tenant Improvements necessary for Tenant’s occupancy of and commencement of business in the respective Buildings or phases, but only to the extent of the actual delay reasonably attributable to the causes or circumstances described herein and directly or proximately caused by such causes or circumstances after the delivery of Landlord’s Structural Completion Certificate for the applicable Building or phase:

(a) Any delay resulting from Landlord’s failure to approve within the time frames required in the Estimated Construction Schedules attached as Exhibit D to the Lease (or, in the case of any requests for which no specific time frame is specified in such Estimated Construction Schedules, within the time frame reasonably specified in writing by Tenant or its construction manager in requesting such approval) any matters requiring approval by Landlord;

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(b) Any delay resulting from any unreasonable or wrongful denial by Landlord or its agents or contractors to Tenant or its agents or contractors of access to the applicable Building or phase, or from any negligent or willful acts or omissions of Landlord or its agents or contractors that interfere materially and unreasonably (beyond reasonable and customary accommodations and coordination issues necessarily involved in the conduct of concurrent work in the applicable premises by Landlord and Tenant) with the actual construction of Tenant’s Work; or

(c) Any delay resulting from changes by Landlord in Landlord’s approved Final Working Drawings and/or Landlord’s Approved Plans that are merely deemed desirable by Landlord without being required by any of the circumstances described in the next to last sentence of Paragraph 2(e)(i) of this Workletter.

11 Financial Information. In August 2002, upon written request by Tenant, Landlord agrees to provide to Tenant, for Tenant’s review, copies of the most recently available financial statements for Landlord and for Landlord’s manager and sole member, Slough Estates USA Inc. Tenant agrees that such financial statements shall be treated as confidential material, and shall not be disseminated to any person or entity (including, but not limited to, any prospective subtenants of Tenant’s existing premises in South San Francisco) without Landlord’s prior written consent, except that Tenant shall be entitled to provide such information, subject to reasonable precautions to protect the confidential nature thereof, to Tenant’s officers, directors and professional advisors, solely to use in connection with Tenant’s analysis and enforcement of its rights under the Lease and this Workletter.

IN WITNESS WHEREOF, the parties have executed this Workletter concurrently with and as of the date of the Lease.

“Landlord”								“Tenant”
SLOUGH BTC, LLC, a Delaware limited liability company								TULARIK INC., a Delaware corporation
By:		Slough Estates USA Inc., a						By:
		Delaware corporation, Its Manager						Its:		CEO
		By:						By:
		Its:		VP				Its:		EVP

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Schedule C-1 to Workletter

BUILDING SHELL

The “Building Shell” as defined in the Workletter to which this Schedule C-1 is attached shall consist of the following:

Building envelope and waterproofing (the Building “shell”), except as specifically indicated as being included in Tenant Improvements under Schedule C-2. including: reinforced grade beam foundation on prestressed concrete piles; ground floor to be reinforced concrete slab supported by concrete piles; second, third and fourth (where applicable) floors to have metal decking with concrete topping slab; roof stucture to be metal deck with concrete for mass dampening in areas to receive mechanical equipment and to include a mechanical penthouse; roof membrane to be built-up system, four-ply including mineral fiber cap sheet, with flashing and sealants; building structural framing to consist of steel beams, girders, columns with a non-bearing exterior curtain wall; seismic system utilizing steel braced frames; floor system designed with live load capacity of 100 psf; roof live load to be 20 psf with minimum of 50 psf (more if required) in all areas within the roofscreen and mechanical penthouse; floor to floor heights of 17 feet, all three (or four) floors.

All other structural work except that driven specifically by Tenant Improvements programming (e.g., interior masonry walls)

Main Building entrances plus 14’ 6” rollup door

Building code required primary structure fireproofing, 1 hour deck at elevated floors

Building code required stairs

Pit and jack for elevator; framed openings at 2^nd and 3^rd floors (and 4th floors where applicable); pits/openings sized for 5’ 8” x 8’ 5” deep inside clear dimension if Tenant provides elevator selection information prior to design completion by Landlord.

Exterior hardscape and landscape, except as specifically included in Tenant Improvements under Schedule C-2

Polyethylene vapor barrier under slab on grade

Site underground water, fire, storm and sanitary service to 5’ outside Building line; sanitary to include monitoring manhole if required by City (but not including any connection, capacity or service fees associated with or imposed in connection with the construction of such manhole)

Building storm and overflow drainage systems

Site underground conduits for “normal” electrical and communications, terminated within the Building, including at least two 4” Pac Bell conduits into Building.

Electrical utility pad and transformer, and primary and secondary service conduits terminated at building switchgear location for Tl-provided electrical service. Sizing for Building shall be a 3000A service, unless not approved by PG&E based on Tenant loads and demands.

Gas service to exterior meter at Building.

Wet fire protection (risers, loops, branches and heads), evenly distributed for “ordinary hazard-group 2” occupancy, including plug T’s to accommodate three branch lines per bay, .20/3000 sf.

Shell design and permitting fees, except as specifically included in Tenant Improvements under Schedule C-2

Vented deck at 2^nd and 3^rd floors

Temporary project fencing

Construction lift for contractor access and stocking of materials (split with TI–50%)

Underslab plumbing and main trunk line for sanitary waste and lab waste (lab waste cost split 50/50 between shell and Tl)

Rigid roof insulation

Site directional signage program; a) “Tularik Main Lobby->”; b) “Tularik shipping/receiving->”; c) “Tularik Building A->’” d) “Tularik Building B->”; e) “Tularik Building->”; E S5.000 allowance by Landlord; balance chargeable to Tenant under TI

Schedule C-2 to Workletter

TENANT IMPROVEMENTS

The “Tenant Improvement” as defined in the Workletter to which this Schedule C-2 is attached may include, but shall not necessarily be limited to, the following:

All tenant construction, design fees, fixtures, furnishings, etc. to support tenant operations, including use space, offices, lobbies, circulation, restrooms and all other features not indicated as part of the Building Shell in Schedule C-1

Service Yard foundations, structure, enclosure and waterproofing

Shipping/receiving/dock equipment and bollards.

Exterior Building skin modifications to support TI systems (e.g., louvers for HVAC accommodation)

Outdoor lounge and eating area

Topical emission barriers at slab on grade, if moisture test exceeds 3 lbs. Vapor barrier to be @ VCT, sheet vinyl and epoxy floor areas only (cost split 50/50 with Shell)

Slab depressions for special finishes or special uses

Enhancement of structure for live loading above 100 PSF or vibration control criteria

Modification of structure for openings at floors and roof

Modification or repair of structure fireproofing required by TI construction

All minor support structures far ducts, conduits, pipes, etc.

Stair enclosures

Stair penthouse, if required

Exterior wall insulation

Firesafing at floor decks, exterior wall and interior openings

Custom doors

Security or other upgrades to exterior doors

Wallboard capture trim at exterior window wall

Visual screens for rooftop equipment

Supports, sleepers, etc. for all rooftop equipment, ducts, plumbing, electrical, etc.

Roof patching for all penetrations relating to Tenant Improvements

Skylights, if used, including curbs, roof patching, etc.

Elevator cab and equipment, except for pit and jack

Shaft walls or other fire separations required for vertical openings (stairs, elevators) or control zones

Distribution/laterals from Building main trunk line for sanitary waste

All underground plumbing (distribution/laterals) and related systems and fixtures for lab waste. Cost of main trunk line for lab waste split 50-50 with shell.

Modifications/enhancements to wet fire protection systems required by TI design

Fire alarm and signal systems

All secondary electrical service for Tenant demand loads, including 3000A main service disconnect, Tenant meter section and distribution panels ‘

Standby electrical generator, if required

Schedule C-2, Page 1 of 2

EXHIBIT E

ACKNOWLEDGMENT OF RENT COMMENCEMENT DATE

This Acknowledgment is executed as of                            , 200            , by SLOUGH BTC, LLC, a Delaware limited liability company (“Landlord”), and TULARIK INC., a Delaware corporation (“Tenant”), pursuant to Section 2.4 of the Build-to-Suit Lease dated December            , 2001 between Landlord and Tenant (the “Lease”) covering premises located at                     Veterans Boulevard, South San Francisco, CA 94080 (the Phase        Building, hereinafter referred to as the “Building”). [In the case of the Phase II Building: This Acknowledgment covers Phase II        of Tenant’s occupancy of the Building.]

Landlord and Tenant hereby acknowledge and agree as follows:

1. The Rent Commencement Date for [Phase II        of] the Building under the Lease is                     , 200    .

2. The termination date under the Lease (if determinable at this time) shall be             , 201    ,subject to any applicable provisions of the Lease for extension or early termination thereof.

3. The square footage of the Building, as finally designed and built, measured in accordance with Sections 1.1 (c) and 3.1 (d) of the Lease, is                square feet. [The square footage of Phase II        of the Phase II Building is                    square feet.]

4. Tenant accepts [Phase II            of] the Building and acknowledges the satisfactory completion of all Improvements thereon required to be made by Landlord, subject only to any applicable “punch list” or similar procedures specifically provided under the Lease or under the Workletter governing such work.

EXECUTED as of the date first set forth above.

FIFTH AMENDMENT TO BUILD-TO-SUIT LEASE

AND SECOND AMENDMENT TO WORKLETTER

THIS FIFTH AMENDMENT TO BUILD-TO-SUIT LEASE AND SECOND AMENDMENT TO WORKLETTER (“Amendment”) is dated as of June 19, 2006 (the “Phase II Lease Commencement Date”) and is entered into by and between SLOUGH BTC, LLC, a Delaware limited liability company (“Landlord”) and AMGEN INC., a Delaware corporation (‘Tenant”), with reference to the following facts:

Recitals

A. Landlord and Tenant (as successor to Tularik Inc.) are parties to (1) a Build-to- Suit Lease dated as of December 20,2001, as amended by that certain First Amendment to Build-to-Suit Lease dated as of January 22, 2003, that certain Second Amendment to Build-to- Suit Lease dated as of March. 26, 2004, that certain Third Amendment to Build-to-Suit Lease dated as of August 12, 2004, and that certain Fourth Amendment to Build-to-Suit Lease and First Amendment to Workletter dated as of June 19, 2006 (collectively, as amended, the “Lease”), covering the [REDACTED] Buildings in Phase I of the Britannia Oyster Point research and development, Center in South San Francisco, California (the “Center”) [REDACTED] (collectively, the “Phase 1 Buildings”), and (2) a Workletter dated as of December 20, 2001, as amended by that certain Fourth Amendment to Build-to-Suit Lease and First Amendment to Workletter dated as of June 19, 2006 (collectively, as amended, the “Workletter”), covering various aspects of the construction of the respective Building Shells for the Phase I Buildings and of the construction of Tenant Improvements in the respective Phase I Buildings. Tenant is already occupying Phase I Buildings A and B; Phase I Building E is under construction for projected occupancy by Tenant on or about January 1,2007; the shell of Phase I Building D has been constructed, and the interior improvements therein will be constructed by Tenant for projected occupancy on or after November 1, 2006.

B. Landlord is in the process of developing the site adjacent to the easterly side of Phase I of the Center as a second phase (“Phase II”) consisting of three additional buildings and related site improvements. A site plan for Phase II is attached to this Amendment as Exhibit A and incorporated herein by this reference (the “Phase II Site Plan”). As used herein, the phrase “Phase II Buildings” refers to Building.A (a four-story steel frame building totaling approximately 115,000 square feet) and Building B (a four-story steel frame building totaling, approximately 122,000 square feet), to be constructed as part of Phase II in approximately the locations designated for them on the Site Plan. Landlord and Tenant wish to add the Phase II Buildings to the Buildings covered by the Lease and to add the Phase II site to the Property covered by the Lease, and in connection therewith to modify certain provisions of the Lease and Workletter and certain of the parties’ respective rights and obligations thereunder, all subject to and as more particularly set forth in this Amendment. This Amendment modifies and amends both the Lease and Workletter, and shall be controlling over any inconsistent provisions of the Lease and Workletter, with respect to the matters, specifically addressed in this Amendment.

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C. Capitalized terms used, in this Amendment as defined terms but not specifically defined in this Amendment shall have the meanings assigned to such terms in the Lease or in the Workletter, as applicable. Notwithstanding the foregoing, the parties note that the phrase “Phase II Building” and related phrases (such as “Phase II Rent Commencement Date”) were used in the Lease as it existed prior to this Amendment to refer to Phase I Building E (1130 Veterans Blvd.) as described above, and that there is some risk of confusion in using the terms “Phase II,” “Phase II Buildings” and similar terms under this Amendment in the manner described in Recital B above. Nevertheless, the parties believe that it is important, for clarity and consistency with the terminology Landlord has used generally in connection with its development of the expansion property described in Recital B above, to adopt the terminology and definitions set forth in Recital B above. Accordingly, the parties hereby confirm and agree, for purposes of clarification, that (1) in connection with the construction and occupancy of Phase I Building E (1130 Veterans Blvd.) as part of the Phase I Buildings as defined above, the Lease and all references therein to “the Phase II Building,” the “Phase II Rent Commencement Date” and similar phrases shall be construed to continue to apply to such Building E in the same manner as they applied prior to adoption of this Amendment, without regard to the provisions of this Amendment, and (2) in connection with the construction and occupancy of Phase II Buildings A and B as the Phase II Buildings as defined above, references in this Amendment and in the Lease as amended hereby to “the Phase II Building(s),” the “Phase II Rent Commencement Date” and similar phrases shall be construed to apply to such Phase II Buildings A and B in accordance with the provisions of this Amendment.

Agreement

NOW, THEREFORE, in consideration of the mutual agreements contained in this Amendment and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Landlord and Tenant agree as follows:

I. Leasing of Phase II Buildings and Amendment of Lease. The two Phase II Buildings (as defined above) are hereby designated as additional Buildings under the Lease and the real property constituting Phase II of the Center, as depicted on the Phase II Site Plan, is hereby added to the Property as defined in the Lease, subject to all of the terms and conditions set forth in this Amendment, and Landlord leases the Phase II Buildings to Tenant and Tenant leases the Phase II Buildings from Landlord on the terms, covenants and conditions set forth in the Lease, as modified by this Amendment and subject to all of the terms and conditions set.forth in this Amendment. Effective upon mutual execution of this Amendment (the date of which mutual execution shall be inserted at the beginning of this Amendment as the Phase II Lease Commencement Date), the Lease shall be deemed to be, and is hereby, amended to reflect and incorporate all of the terms and conditions set forth in this Amendment. In the event of any inconsistency between provisions of the Lease and provisions of this Amendment, the provisions of this Amendment shall be controlling with respect to the matters specifically addressed in this Amendment.

(a) Except as otherwise expressly provided herein, Tenant’s Minimum Rental and Operating Expense obligations with respect to the Phase II Buildings shall commence on the earlier to occur of (i) the date which is three hundred sixty (360) days after the date Landlord delivers to Tenant a Structural Completion Certificate for the Phase II Buildings pursuant to the

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Workletter, subject to any adjustments in such time period to the extent authorized or required under the provisions of the Workletter, or (ii) the date Tenant takes occupancy of and commences operation of its business in any material portion of the Phase II Buildings (the ‘’Phase II Rent Commencement Date”); provided, however, that if Landlord delivers (or is deemed to deliver) the Structural Completion Certificates for the respective Phase II Buildings on different dates, or if Tenant commences operation of its business in the respective Phase II Buildings on different dates, then the Phase II Rent Commencement Date shall be determined separately for each of the respective Phase II Buildings pursuant to the provisions of clauses (i) and (ii) above, applied separately and independently with respect to each Phase II Building. Based on the milestone construction schedule and the draft detailed Master Schedule (6/1/06) collectively attached hereto as Exhibit B (the “Milestone Construction Schedule”), the parties presently estimate that the Phase II Rent Commencement Date will occur on or about November 1, 2008. The Termination Date for Tenant’s leasing of the Phase II Buildings shall be the day immediately preceding the fifteenth (15^th) anniversary of the Phase II Rent Commencement Date (or, if there are different Rent Commencement Dates for the respective Phase II Buildings, the day immediately preceding the fifteenth (15^lh) anniversary of the later of such Phase II Rent Commencement Dates to occur), unless sooner terminated or extended as hereinafter provided. Consistent with Recital C above, the provisions of Section 2.1(b) of the Lease (regarding phased occupancy of and phased rent commencement for the “Phase II Building” as defined in the original Lease) shall be construed to apply solely to Phase 1 Building E (1130 Veterans Blvd.) as described above, and shall be inapplicable to the Phase II Buildings as defined in this Amendment.

(b) The Milestone Construction Schedule is predicated on execution of this Amendment and release of project teams by Landlord on June 1, 2006. To the extent that such execution and release are delayed materially beyond June 1, 2006, the dates set forth in the Milestone Construction Schedule may be affected by such delay. In any event, the Milestone. Construction Schedule as attached hereto is merely preliminary and non-binding in nature. A draft of a detailed master construction schedule (similar to the schedules attached as Exhibit D to the original Lease) for the Phase II Buildings as of June 1, 2006, including milestone dates outlining specific Landlord and Tenant responsibilities, is attached hereto as the second page of the Milestone Construction Schedule. Following the Phase II Lease Commencement Date, Landlord and Tenant shall cooperate reasonably, diligently and in good faith to achieve mutual approval of such detailed construction schedule (which shall then be referred to as the ‘‘Approved Construction Schedule”), including any mutually agreeable modifications to such draft schedule. Thereafter, references in the Lease and Workletter (as amended hereby) to the Estimated Construction Schedule shall, with respect to the Phase II Buildings, be construed to refer to such Approved Construction Schedule. Notwithstanding anything to the contrary in Section 10.1 of the Lease, Tenant’s obligation under Section 10.1 for payment of all charges for services and utilities supplied to or consumed in or with respect to the respective Phase II Buildings, including any taxes on such services and utilities, shall commence on the date Landlord delivers the Structural Completion Certificate for the applicable Phase II Building to Tenant.

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(c) Beginning on the Phase II Rent Commencement Date for the applicable Phase II Building and continuing through the Termination Date for the initial Term of the Lease with respect to the Phase II Buildings, Tenant’s monthly Minimum Rental obligation for each Phase II Building pursuant to Section 3.1(a) of the Lease shall be equal to the applicable amount per square foot from the following table multiplied by the square footage of the applicable Phase II Building as determined pursuant to Section 3.1(d) of the Lease:

[REDACTED]

(d) Notwithstanding any provisions of Section 3.1 (b), (c) and/or (e) of the Lease to the contrary:

(i) If Tenant properly exercises its right under Section 2.6 of the Lease to one or both extended terms with respect to the Phase II Buildings, the Minimum Rental for each Phase II Building during the first year of each applicable extended term shall be one hundred four percent (104%) of the Minimum Rental payable for such Phase II Building during the last full month of the lease year immediately preceding the commencement of the applicable extended term, and such Minimum Rental shall be further increased on each anniversary of the commencement of the applicable extended term to one hundred four percent (104%) of the Minimum Rental payable for such Phase II Building during the last full month of the immediately preceding lease year of the applicable extended term.

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(ii) The entire Tenant Improvement Allowance for the Phase II Buildings as described in Section.2(c) of this Amendment has already been taken into account in establishing the Minimum Rental rates set forth above. Accordingly, the “additional rent” provisions set forth in Section 3.1(e) of the Lease are inapplicable to the Phase II Buildings and Tenant shall have no liability for any additional rent under Section 3.1 (e) of the Lease with respect to the Phase II Buildings.

(e) Landlord’s intention is to calculate and allocate Operating Expenses for Phase II of the Center separately from and independently of the calculation and allocation of Operating Expenses for Phase I of the Center. Tenant’s Operating Cost Share (as such term is used in the Lease) with respect to each Phase II Building shall be 100% for Operating Expenses which are allocable solely to such Phase II Building, and (subject to the assumption set forth in the preceding sentence) for Operating Expenses which are allocated on a Phase II-wide basis, shall for each Phase II Building be equal to the percentage share calculated by dividing the square footage of such Phase II Building (determined on the basis of measurement set forth in Section 1.1(c) of the Lease) by the aggregate square footage of all three (3) Buildings in Phase II of the Center (similarly and consistently determined on the basis of measurement set forth in Section 1.1(c) of the Lease). The foregoing shares do not include the Operating Cost Shares attributable to any of the Phase I Buildings, which shall continue to be calculated under the Lease in a manner consistent with prior practice, and Tenant’s payment obligations arising from the Operating Cost Shares for the Phase II Buildings as described above shall simply be added to the payment obligations arising from the Operating Cost Shares for the Phase I Buildings in determining Tenant’s total payment obligations for Operating Expenses under the Lease, All such Operating Cost Shares with respect to the Phase II Buildings shall remain subject to adjustment under the circumstances and to the extent set forth in the Lease, and shall be subject to the following additional provisions, notwithstanding anything to the contrary contained in the Lease or elsewhere in this Amendment:

(i) For purposes of calculating Tenant’s Operating Cost Share of Operating Expenses which are allocated on a Phase II-wide basis, the aggregate square footage of all three (3) Buildings constructed or to be constructed in Phase II of the Center shall be included as if all three (3) such Buildings (including, but not limited to, Building C as designated on the Phase II Site Plan) were fully built-out at the time Tenant’s obligation with respect to Operating Expenses for the Phase II Buildings commences.

(ii) Solely during the first two (2) years following the date on which Tenant’s obligation for payment of Operating Expenses with respect to the Phase II Buildings commences, Tenant’s Operating Cost Share for each Phase II Building shall be based solely on the square footage actually used or occupied by Tenant in that Phase II Building, so that Tenant’s Operating Cost Share for Operating Expenses allocated solely to that Phase II Building shall be equal to the square footage actually used or occupied by Tenant in that Phase II Building divided by the total square footage of that Phase II Building, and Tenant’s Operating Cost Share for Operating Expenses allocated on a Phase II-wide basis shall be equal to the square footage actually used or occupied by Tenant in that Phase II Building divided by the total square footage of all three (3) Buildings constructed or to be constructed in Phase II of the Center, as provided in subparagraph (i) above.

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(f) To the extent (if any) that Landlord already holds a security deposit or deposits under the Lease with respect to the Phase I Buildings, such existing deposit(s), whether in the form of a cash deposit or a Letter of Credit, shall also be deemed to be useable by Landlord, under the provisions of the Lease, in connection with any defaults by Tenant relative to its leasing and occupancy of the Phase II Buildings pursuant to the Lease as amended hereby, but no additional or increased security deposit shall be required from Tenant with respect to the addition of the Phase II Buildings to the Buildings pursuant to this Amendment.

(g) Notwithstanding the provisions of Section 21.20(b) of the Lease, (i) Phase II of the Center is presently intended to contain approximately 2.8 parking spaces per 1,000 square feet of rentable area in the buildings to be constructed in Phase II of the Center, which ratio shall be used in allocating nonexclusive parking spaces to Tenant under Section 21.20 of the Lease with respect to the Phase II Buildings, and (ii) the monthly fee per parking space allocable to each Phase II Building shall be [REDACTED] per parking space for the first five (5) years after the Phase II Rent Commencement Date for such Building, [REDACTED] per parking space for years six (6) through ten (10) after the Phase II Rent Commencement Date for such Building, and [REDACTED] per parking space thereafter.

(h) Solely as applied to the Phase II Buildings, the first sentence of Section 11.1 of the Lease is amended to read as follows:

“Tenant shall make no alterations, additions or improvements to any Phase II Building without the prior written consent of Landlord, which consent shall not be unreasonably withheld, conditioned or delayed, except that (i) subject to the final sentence of this Section 11.1 (regarding structural or roof alterations, substantial equipment installations on the roof, or alterations to building systems), Tenant shall not be required to obtain such consent for interior alterations costing less than One Hundred Thousand Dollars ($100,000.00) for any single project (i.e., any single item of alterations or set of related alterations in a Phase II Building), and (ii) regardless of whether Landlord’s consent would otherwise be required under this Lease, Tenant shall provide Landlord with prior written notice of any proposed alterations, additions or improvements having a cumulative estimated cost of more than Four Hundred Thousand Dollars ($400,000.00) in any twelve (12) month period.”

(i) Supplementing the provisions of Article 15 of the Lease with respect to assignment and subleasing, Landlord and Tenant agree that with respect to the Phase II Buildings, in the case of any assignment or subleasing other than a Permitted Transfer as defined in Section 15.1 of the Lease, the following provisions shall apply:

(i) Upon any assignment of Tenant’s interest in the Lease for which Landlord’s consent is required under Section 15.1 of the Lease, Tenant shall pay to Landlord, within ten (10) days after receipt thereof by Tenant from time to time, one-half ( ¹⁄₂) of all cash sums and other economic considerations received by Tenant in connection with or as a result of such assignment, after first deducting therefrom (i) any costs incurred by Tenant for leasehold improvements (including, but not limited to, third-party architectural and space planning costs) in the Premises in connection with such assignment, amortized over the remaining term of this Lease, and (ii) any reasonable real estate commissions and/or reasonable attorneys’ fees actually incurred by Tenant in connection with such assignment.

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(ii) Upon any sublease of all or any portion of a Phase II Building for which Landlord’s consent is required under Section 15.1 of the Lease, Tenant shall pay to Landlord, within ten (10) days after receipt thereof by Tenant from time to time, one-half ( ¹⁄₂) of all cash sums and other economic considerations received by Tenant in connection with or as a result of such sublease, after first deducting therefrom (i) the minimum rental due under the Lease for the applicable Phase II Building for the corresponding period, prorated (on the basis of the average per-square-foot cost paid by Tenant for such Phase II Building for the applicable period under the Lease) to reflect the size of the subleased portion of such Phase II Building, (ii) any costs incurred by Tenant for leasehold improvements in the subleased portion of such Phase II Building (including, but not limited to, third-party architectural and space planning costs) for the specific benefit of the sublessee in connection with such sublease, amortized over the remaining term of the Lease, and (iii) any reasonable real estate commissions and/or reasonable attorneys’ fees actually incurred by Tenant in connection with such sublease, amortized over the term of such sublease.

2. Construction Amendment of Workletter. The parties intend and agree that the construction of the Phase II Buildings and of the Tenant Improvements necessary for Tenant’s occupancy and use thereof shall be governed by and performed in accordance with the provisions of the Workletter, subject to all of the terms and conditions set forth in this Amendment. Effective upon the Phase II Lease Commencement Date, the Workletter shall be deemed to be, and is hereby, amended to reflect and incorporate all of the terms and conditions set forth in this Amendment. In the event of any inconsistency between provisions of the Workletter and provisions of this Amendment, the provisions of this Amendment shall be controlling with respect to the matters specifically addressed in this Amendment. Without limiting the generality of the foregoing, Schedule C-1 and Schedule C-2 attached hereto shall supersede, with respect to the Phase II Buildings, the comparable schedules attached to the Workletter.

(a) The Building Shell for each Phase II Building shall be constructed by Landlord in accordance with (i) Article 5 of the Lease, (ii) the Workletter (as amended hereby), and (iii) the shell definition set forth in Schedule C-1 attached hereto and incorporated herein by this reference. Landlord acknowledges that pursuant to the foregoing provisions, (i) Landlord and Landlord’s Architect shall be responsible for code compliance (including, but not limited to, compliance with any applicable requirements of the Americans with Disabilities Act and any applicable similar or related requirements pertaining to access by persons with disabilities) with respect to the Building Shell and any other improvements designed by Landlord, and (ii) all Phase II Building improvements and site improvements constructed by Landlord in Phase II of the Center shall be constructed (A) free of hazardous substances (as defined in Section 13.6(a) of the Lease), asbestos, asbestos-containing materials and presumed asbestos-containing materials, and (B) in compliance in all material respects with all applicable federal and state laws and requirements relating to hazardous substances.

(b) The Tenant Improvements for each Phase II Building shall be constructed by Tenant (and/or by Landlord, if applicable) in accordance with (i) Article 5 of the Lease, (ii) the Workletter (as amended hereby), and (iii) the tenant improvements definition set forth in Schedule C-2 attached hereto and incorporated herein by this reference, subject to any alternative arrangements mutually approved in writing by Landlord and Tenant from time to time. Tenant acknowledges that pursuant to the foregoing provisions, Tenant and Tenant’s

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Architect shall be responsible for code compliance (including, but not limited to, compliance with any applicable requirements of the Americans with Disabilities Act and any applicable similar or related requirements pertaining to access by persons with disabilities) with respect to any and all improvements designed by Tenant or Tenant’s Architect. Without limiting the breadth of the approval rights otherwise reserved to Landlord under the Workletter, Landlord reserves the right, in reviewing Tenant’s proposed drawings and specifications at any stage, to require specific modifications to the proposed Tenant Improvements, at no material additional cost to Tenant, in order to maintain or enhance flexibility with respect to other potential future uses of the Phase II Buildings. Tenant shall have the right to provide, install and maintain, at its sole cost and expense, a security system (including, without limitation, automatic door latches, card-key systems, cameras, etc.) in the Phase II Buildings, which security system shall be surrendered to Landlord upon expiration or termination of the Lease with respect to such Phase II Buildings and Tenant shall have no obligation to restore or remove such security system. Tenant shall provide Landlord and its property manager with copies of any card-keys or other required access devices in order to facilitate emergency entry by Landlord or its agents during the term of the Lease, subject to the provisions of Section 16.1 of the Lease.

(c) [REDACTED] Under no circumstances shall the Tenant Improvement Allowance or any portion thereof be used or useable for any moving or relocation expenses of Tenant, or for any Cost of Improvement (or any other cost or expense) associated with any moveable furniture, trade fixtures, personal property or any other item or element which, under the applicable provisions of the Lease, will not become Landlord’s property and remain with the applicable Phase II Building upon expiration or termination of the Lease. The provisions in Paragraph 4(b) of the Workletter regarding relative proportions of laboratory space and office space in the Buildings shall be inapplicable to the Phase II Buildings, and without limiting the generality of the foregoing, Landlord specifically agrees that the relative proportions of office space (if any) and/or laboratory space (if any) in the respective Phase II Buildings shall have no adverse effect on the amount of the Tenant Improvement Allowance for the Phase II Buildings as described above.

(d) Unless and until revoked by Landlord by written notice delivered to Tenant, Landlord hereby (i) delegates to Project Management Advisors, Inc., or any other project manager designated by Landlord in its sole discretion from time to time by written notice to Tenant (“Project Manager”), the authority to exercise all approval rights and other rights and powers of Landlord under the Workletter with respect to the design and construction of the Building Shell and Tenant Improvements for the Phase II Buildings, and (ii) requests that Tenant work with Project Manager with respect to any logistical or other coordination matters arising in the course of construction of the respective Building Shells and Tenant Improvements, including

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(but not limited to) reviewing and processing Tenant’s requests for disbursement of the Tenant improvement Allowance, monitoring Tenant’s and Landlord’s compliance with their respective obligations under the Workletter and under the Lease (as amended hereby) with respect to the design and construction of the Building Shell and the Tenant Improvements, and addressing any coordination issues that may arise in the course of construction of the Building Shell and Tenant Improvements. Tenant acknowledges the foregoing delegation and request, and agrees to cooperate reasonably with Project Manager as Landlord’s representative pursuant to such delegation and request. As between Landlord and Tenant, however, Landlord shall be bound by and be fully responsible for all acts and omissions of Project Manager and for the performance of all of Landlord’s obligations under the Lease (as amended hereby) and the Workletter, notwithstanding such delegation of authority to Project Manager. Notwithstanding the preceding sentence, neither Landlord’s delegation of authority to Project Manager nor Project Manager’s performance of the functions and responsibilities contemplated in this paragraph shall cause Landlord or Project Manager to incur any obligations or responsibilities for the design, construction or delivery of the Tenant Improvements, except to the extent of the specific obligations and responsibilities of Landlord expressly set forth in the Lease (as amended hereby) and in the Workletter. [REDACTED]

(e) Notwithstanding anything to the contrary contained in Section 14.1(e) of the Lease or in the Workletter, the builder’s risk insurance contemplated in such Section 14.1(e) for the Tenant Improvements constructed by Tenant in the Phase II Buildings pursuant to this Amendment and the Workletter shall be maintained by Tenant, at Tenant’s sole expense, and shall otherwise comply with all applicable requirements under such Section 14.1(e).

[REDACTED]

[REDACTED]

[REDACTED]

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[REDACTED]

[REDACTED]

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[REDACTED]

4. Brokers. Each party respectively (i) represents and warrants that no broker participated in the consummation of this Amendment or of the transactions contemplated herein, and (ii) agrees to indemnify, defend and hold the other party harmless against any liability, cost or expense, including (but not limited to) reasonable attorneys’ fees, arising out of any claims for brokerage commissions or other similar compensation by any broker or agent alleging to have acted on behalf of the indemnifying party in connection with this Amendment and the transactions contemplated herein. The provisions of Section 21.15 of the Lease (Brokers) do not apply to this Amendment or the transactions contemplated herein.

5. Publicity. Neither party will make any press release or other media, promotional or advertising disclosure regarding this Amendment or the transactions contemplated hereby without the other party’s express prior written consent, except as required under applicable law or by any governmental agency. Without limiting the generality of the foregoing, each party agrees that the other party will have no less than five (5) business days to review and provide comment regarding any such proposed press release or publicity regarding this Amendment or the transactions contemplated hereby, unless a shorter review time is agreed to by both parties. In the event that one party reasonably concludes that a given disclosure is required by law and the other party would prefer not to make such disclosure, then the party seeking such disclosure shall either (i) limit said disclosure to address the concerns of the other party, or (ii) provide a written opinion from counsel stating that such disclosure is indeed required by law. With respect to complying with the disclosure requirements of the SEC or other, securities regulatory bodies in other nations, in connection with any required securities filing of this Amendment the filing, party shall seek confidential treatment of this Amendment to the maximum extent permitted by such regulatory body and shall provide the other party with the opportunity, for at least fifteen (15) days, to review any such proposed filing. Each party agrees that it will obtain its own legal advice with regard to its compliance with securities laws and regulations, and will not rely on any statements made by the other party relating to such securities laws and regulations. Further, Landlord shall not use the name of Tenant, its affiliates or products or any signs, markings, or symbols from which a connection to Tenant, in Tenant’s sole judgment, may be reasonably inferred or implied, in any manner whatsoever, including, without limitation, press releases, marketing materials, and advertisements, without Tenant’s prior written approval. Tenant may withhold approval at Tenant’s sole discretion. Nothing in this paragraph, however, is intended or shall be construed to prohibit, or to require Tenant’s approval for, Landlord’s inclusion of Tenant’s name and of pertinent business terms of the Lease (as amended hereby) on any rent rolls, tenant lists or other similar documents that Landlord may submit from time to time to any lender or prospective lender, purchaser or prospective purchaser, or governmental or quasi-

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governmental authority in connection with Landlord’s ownership and operation of the Center, but only to the extent that Landlord determines in its sole discretion that such disclosure is reasonably necessary in order to advance Landlord’s dealings with the applicable lender, purchaser and/or governmental or quasi-governmental authority, and then only to the extent that disclosure of comparable information is concurrently being made with respect to other tenants of the Center.

6. Entire Agreement. This Amendment constitutes the entire agreement between Landlord and Tenant regarding the subject matter hereof and supersedes all prior negotiations, discussions, terms sheets, letters, understandings and agreements, whether oral or written, between the parties with respect to such subject matter (other than the Lease itself, as expressly amended, hereby).

7. Execution and Delivery. This Amendment may be executed in one or more counterparts and by separate parties on separate counterparts, effective when each party has executed at least one such counterpart or separate counterpart, but each such counterpart shall constitute an original and all such counterparts together shall constitute one and the same instrument.

8. Full Force and Effect. Except as expressly set forth herein, the Lease has not been modified or amended and remains in full force and effect.

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IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as of the date first set forth above.

“Landlord”								“Tenant”
SLOUGH BTC, LLC, a Delaware limited liability company								AMGEN INC., a Delaware corporation
By:		Slough Estates USA Inc., a Delaware corporation, Its Manager						By: /s/ Michael A. Kelly
								Name: Michael A. Kelly
								Title: VP Corporate Planning & Control, CA
		By: /s/ Jonathan M. Bergschneider
		Name: Jonathan M. Bergschneider
		Title: Vice President

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EXHIBIT A

PHASE II SITE PLAN

[See attached page.]

EXHIBIT A to Fifth Amendment

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EXHIBIT B

MILESTONE CONSTRUCTION SCHEDULE

Milestone construction schedule for Britannia Oyster Point Phase II (333 Oyster Point Blvd.), Buildings A and. B, assuming a June 1,2006 release date, and subject to review and mutual approval of the detailed master construction schedule attached as the following page hereof (including any mutually agreed modifications thereto) as provided in the Lease, as amended:

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EXHIBIT B to Fifth Amendment (Page 1 of 2)

Schedule C-1

PHASE II BUILDINGS SHELL DESCRIPTION

The “Building Shell” as used in the Amendment to which this Schedule C-1 is attached and in the Workletter described therein shall consist of the following:

Building envelope and waterproofing (the Building “shell”), except as specifically indicated as being included in Tenant Improvements under Schedule C-2, including: two levels of below “street level” parking supported on reinforced concrete shallow foundations and constructed of steel and concrete structural elements; elevated, floors of metal decking with concrete fill; roof structure of metal deck with concrete fill; roof membrane to be a built-up system, with rigid insulation, flashing and sealants; building structural framing to consist of steel beams, girders, columns with a non-load-bearing exterior curtain wall; seismic system utilizing steel braced frames and concrete shear walls; roof live load to be 20 PSF with 75 PSF in all areas within the roofscreen (roofscreen loading is non-reducible); floor to floor heights within the Shell Buildings (superstructure) of 17 feet, all floors

All other structural work except that driven specifically by Tenant Improvements programming (e.g., interior masonry walls)

Floor designed for 100 PSF uniform live load capacity (reducible as allowed by code)

Main Building entrance(s)

Building code required primary structure fireproofing

Building code required stairs. Stair enclosures & handrails at lower level parking only

Pit and floor openings for one elevator

Exterior hardscape and landscape, except as specifically indicated as included in Tenant Improvements under Schedule C-2

Two-level steel and concrete parking structure beneath the Shell (superstructure) Buildings

Site underground water, fire, storm and sanitary service to 5 feet outside Building line

Building storm and overflow drainage systems

Site underground conduits for “normal” electrical and communications, terminated within the parking structure beneath each Shell Building

Electrical utility pad and transformer, primary service conduits terminated at Shell building switchgear location (within the parking structure beneath each Shell Building) for TI-provided electrical service

Gas service up to exterior meter location at each Building (but not including meter)

Wet fire protection (risers, loops, branches and heads), evenly distributed for “ordinary hazard, group 2” occupancy

Shipping/receiving dock and services room and foundation within garage envelope

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Schedule C-1 Page 1 of 2

Shell design and permitting fees, except as specifically included in Tenant Improvements under Schedule C-2

Vented deck at upper floors

Temporary project fencing

Construction lift for contractor safety, access, and stocking of materials (split with TI—50%)

Underslab sanitary waste main trunk line (split with TI—50%; branch distribution by TI)

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Schedule C-1– Page 2 of 2

Schedule C-2

PHASE II BUILDINGS TENANT IMPROVEMENTS DESCRIPTION

The “Tenant Improvements” as defined in the Amendment to which this Schedule C-2 is attached and in the Workletter described therein shall include, but not necessarily be limited to, the following, to be constructed from Tenant Improvement Allowance funds or otherwise at Tenant’s expense:

All tenant construction, design fees, fixtures, furnishings, etc. to support tenant operations, including use space, offices, lobbies, circulation, restrooms and all other features not specifically indicated as part of the Building Shell in Schedule C-I

Foundations, structure, enclosure and waterproofing for emergency generator and trash enclosure.

Any service area that is included in the area (square footage) calculation for the applicable Building, and upon which rent is therefore paid by Tenant, will not fall under this definition for purposes of this schedule. [1]

Exterior building skin modifications to support TI systems (e.g., louvers for HVAC accommodation) [2]

Outdoor lounge and eating area [2]

Topical emission barriers on slabs, if required

Slab depressions for special finishes or special uses [2]

Enhancement of structure for live loading above 100 PSF or vibration control criteria [2]

Modification of structure for openings at floors and roof [2]

Modification or repair of structure fireproofing required by TI construction

All minor support structures for ducts, conduits, pipes, etc.

Stair enclosures, vestibule doors, dedicated mechanical shafts & ducts for stair pressurization, handrails and guardrails (except at parking levels, per Schedule C-1) [1]

Mechanical equipment, controls & monitoring, ductwork and penetrations required to pressurize stairs in advance of occupancy. per South San Francisco code. [1]

Stair penthouse, if required [1]

Exterior wall insulation

Firesafing at floor decks, exterior walls and interior openings [performed under Method 1 only if required during shell construction by City of SSF, otherwise performed by TI contractor)[1]

Custom doors

Security or other upgrades to exterior doors

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Schedule C-2– Page 1 of 3

Wallboard capture trim at exterior window wall

Visual screens and supporting structures/platforms/sleepers, etc. for rooftop equipment, ducts, plumbing, electrical, etc. [1]

Roof patching for all penetrations relating to Tenant Improvements

Skylights, if used, including curbs, roof patching, etc.

Elevator cab and equipment, except for one pit and floor openings. Additional elevators by Tenant.

Shaft walls or other fire separations in buildings required for vertical openings (stairs, elevators) or control zones

Distribution/laterals from sanitary waste main trunk line (main trunk line splot with Shell 50%)

All lab waste plumbing and related systems and fixtures, if required

Gas meter and piping from gas meter to Building

Modifications/enhancements to wet^;fire protection systems required by TI design

Fire alarm, signal and security systems (some of which may need to be installed as part of the Shell due to code requirements [Method 1 below], in which event they will be charged against the TI Allowance);

All secondary electrical service for Tenant demand loads, including main service disconnect, Tenant meter section and distribution panels

Standby electrical generator, if required

All electrical communications wire and service not specifically included in Building Shell

All TI design fees and reimbursables

All other “soft” costs, including TI permit/development fees, utility capacity or connection charges, etc.

Landlord-provided oversight of TI activities as specified in Amendment and Workletter

All testing and inspection of TI construction

Builders risk insurance for TI construction including earthquake coverage

All general contractor preconstruction services costs related to TI construction

Construction lift for contractor safety, access and stocking of materials (split with shell–50%)

“Tenant Improvements” shall not include the design and/or construction of infrastructure, landscaping or other site improvements unless specifically requested by Tenant or as a result of Tenant Improvements or Tenant’s requested modifications to existing plans

Elements shown in bold and underlined will be implemented in accordance with Page 3 of this Schedule C-2 and charged against the Tenant Improvement Allowance.

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Schedule C-2– Page 2 of 3

IMPLEMENTATION METHODS FOR WORK CONSTRUCTED BY LANDLORD

ON BEHALF OF TENANT AT TENANT’S EXPENSE

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Schedule C-2 – Page 3 of 3

EXHIBIT B

PREMISES

EXHIBIT C

WARM SHELL CONDITION

Britannia Oyster Point Sublease

Summary Scope of Warm Shell

Lobby

Stairways

Elevators

Restrooms and Showers

Mechanical/Electrical Design Criteria

HVAC Units

Exhaust Fans

Hot Water

Industrial Cold Water

Potable Hot and Cold Water

Building Automation System

Natural Gas

Sanitary Waste

Laboratory Waste

Electrical

Life Safety System

Telecommunications

Not Included as part of the Warm Shell Condition:

EXHIBIT D

[INTENTIONALLY DELETED]

EXHIBIT E

FORM OF LETTER OF CREDIT

IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVBSF             

AMOUNT: US$2,249,126.88 (TWO MILLION TWO HUNDRED FORTY NINE THOUSAND ONE HUNDRED TWENTY SIX AND 88/100 U.S. DOLLARS)

EXPIRATION DATE:                      [1 YR. FROM ISSUE DATE]

LOCATION: SANTA CLARA, CALIFORNIA

GENTLEMEN:

WE HEREBY ESTABLISH OUR IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVBSF                      IN YOUR FAVOR FOR THE ACCOUNT OF THE ABOVE-REFERENCED APPLICANT IN THE AGGREGATE AMOUNT OF EXACTLY TWO MILLION TWO HUNDRED FORTY NINE THOUSAND ONE HUNDRED TWENTY SIX AND 88/100 U.S. DOLLARS (US$2,249,126.88) AVAILABLE BY YOUR SIGHT DRAFTS DRAWN ON US IN THE FORM OF EXHIBIT “A” ATTACHED AND ACCOMPANIED BY THE FOLLOWING:

1. THE ORIGINAL LETTER OF CREDIT AND ALL AMENDMENTS, IF ANY.

2. BENEFICIARY’S DATED STATEMENT SIGNED BY AN AUTHORIZED SIGNATORY OF BENEFICIARY, STATING:

OR

OR

OR

THE SUBLEASE AGREEMENT MENTIONED ABOVE IS FOR IDENTIFICATION PURPOSES ONLY AND IT IS NOT INTENDED THAT SAID SUBLEASE AGREEMENT BE INCORPORATED HEREIN OR FORM PART OF THIS LETTER OF CREDIT.

PARTIAL AND MULTIPLE DRAWINGS ARE ALLOWED. THIS LETTER OF CREDIT MUST ACCOMPANY ANY DRAWINGS HEREUNDER FOR ENDORSEMENT OF THE DRAWING AMOUNT AND WILL BE RETURNED TO THE BENEFICIARY UNLESS IT IS FULLY UTILIZED.

THIS LETTER OF CREDIT SHALL BE AUTOMATICALLY EXTENDED FOR AN ADDITIONAL PERIOD OF ONE YEAR, WITHOUT AMENDMENT, FROM THE PRESENT OR EACH FUTURE EXPIRATION DATE UNLESS AT LEAST 30 DAYS PRIOR TO THE THEN CURRENT EXPIRATION DATE WE NOTIFY YOU BY REGISTERED MAIL OR OVERNIGHT COURIER SERVICE AT THE ABOVE ADDRESS (OR ANY OTHER ADDRESS INDICATED BY YOU, IN A WRITTEN NOTICE TO US THE RECEIPT OF WHICH WE HAVE ACKNOWLEDGED, AS THE ADDRESS TO WHICH WE SHOULD SEND SUCH NOTICE) THAT THIS LETTER OF CREDIT WILL NOT BE EXTENDED BEYOND THE CURRENT EXPIRATION DATE. IN NO EVENT SHALL THIS LETTER OF CREDIT BE AUTOMATICALLY EXTENDED BEYOND APRIL 29, 2024 WHICH SHALL BE THE FINAL EXPIRATION DATE OF THIS LETTER OF CREDIT.

THIS LETTER OF CREDIT IS TRANSFERABLE ONE OR MORE TIMES, BUT IN EACH INSTANCE ONLY IN ITS ENTIRETY AND ONLY UP TO THE THEN AVAILABLE AMOUNT, ASSUMING SUCH TRANSFER TO SUCH TRANSFEREE WOULD BE IN COMPLIANCE WITH THEN APPLICABLE LAW AND REGULATION, INCLUDING BUT NOT LIMITED TO THE REGULATIONS OF THE U. S. DEPARTMENT OF TREASURY AND U. S. DEPARTMENT OF COMMERCE. BENEFICIARY MAY, AT ANY TIME, AND WITHOUT FIRST OBTAINING APPLICANT’S CONSENT THERETO, TRANSFER ALL OF BENEFICIARY’S INTEREST IN THE LETTER OF CREDIT TO ANOTHER PARTY,

PERSON OR ENTITY. AT THE TIME OF TRANSFER, THE ORIGINAL LETTER OF CREDIT AND ORIGINAL AMENDMENT(S), IF ANY, MUST BE SURRENDERED TO US AT OUR ADDRESS INDICATED IN THIS LETTER OF CREDIT TOGETHER WITH OUR TRANSFER FORM ATTACHED HERETO AS EXHIBIT “B” DULY EXECUTED. OUR TRANSFER FEE OF  ¹⁄₄ OF 1% OF THE TRANSFER AMOUNT (MINIMUM US$250.00) SHALL BE CHARGED TO THE ACCOUNT OF THE APPLICANT. THE CORRECTNESS OF THE SIGNATURE AND TITLE OF THE PERSON SIGNING THE TRANSFER FORM MUST BE VERIFIED BY BENEFICIARY’S BANK. ANY TRANSFER OF THIS LETTER OF CREDIT MAY NOT CHANGE THE PLACE OF EXPIRATION OF THE LETTER OF CREDIT FROM OUR ABOVE-SPECIFIED OFFICE. EACH TRANSFER SHALL BE EVIDENCED BY OUR ENDORSEMENT ON THE REVERSE OF THE ORIGINAL LETTER OF CREDIT AND WE SHALL FORWARD THE ORIGINAL LETTER OF CREDIT TO THE TRANSFEREE.

DRAFT(S) AND DOCUMENTS MUST INDICATE THE NUMBER AND DATE OF THIS LETTER OF CREDIT.

WE HEREBY AGREE WITH YOU THAT DRAFTS DRAWN UNDER AND IN COMPLIANCE WITH THE TERMS OF THIS LETTER OF CREDIT WILL BE DULY HONORED UPON PRESENTATION TO US AT OUR OFFICE LOCATED AT: 3003 TASMAN DRIVE, SANTA CLARA, CA 95054 ATTENTION: STANDBY LETTER OF CREDIT NEGOTIATION SECTION, WITHOUT INQUIRY AS TO THE ACCURACY THEREOF AND REGARDLESS OF WHETHER APPLICANT DISPUTES THE CONTENT OF SUCH DOCUMENTS OR STATEMENTS OR BY FACSIMILE TRANSMISSION AT: (408) 969-6510 OR ###-###-#### AND SIMULTANEOUSLY UNDER TELEPHONE ADVICE TO: (408) 654-7176 OR ###-###-####, ATTENTION: STANDBY LETTER OF CREDIT NEGOTIATION SECTION WITH ORIGINALS TO FOLLOW BY OVERNIGHT COURIER SERVICE; PROVIDED, HOWEVER, THE BANK WILL DETERMINE HONOR OR DISHONOR ON THE BASIS OF PRESENTATION BY FACSIMILE ALONE, AND WILL NOT EXAMINE THE ORIGINALS.

IF ANY INSTRUCTIONS ACCOMPANYING A DRAWING UNDER THIS LETTER OF CREDIT REQUEST THAT PAYMENT IS TO BE MADE BY TRANSFER TO YOUR ACCOUNT WITH ANOTHER BANK, WE WILL ONLY EFFECT SUCH PAYMENT BY FED WIRE TO A U.S. REGULATED BANK, AND WE AND/OR SUCH OTHER BANK MAY RELY ON AN ACCOUNT NUMBER SPECIFIED IN SUCH INSTRUCTIONS EVEN IF THE NUMBER IDENTIFIES A PERSON OR ENTITY DIFFERENT FROM THE INTENDED PAYEE.

THIS LETTER OF CREDIT IS SUBJECT TO THE INTERNATIONAL STANDBY PRACTICES ISP98, INTERNATIONAL CHAMBER OF COMMERCE, PUBLICATION NO. 590 (“ISP98”).

SILICON VALLEY BANK,

EXHIBIT “A”

SIGHT DRAFT/BILL OF EXCHANGE

GUIDELINES TO PREPARE THE SIGHT DRAFT OR BILL OF EXCHANGE:

NOTE: BENEFICIARY SHOULD ENDORSE THE BACK OF THE SIGHT DRAFT OR BILL OF EXCHANGE AS YOU WOULD A CHECK.

IF YOU NEED FURTHER ASSISTANCE IN COMPLETING THIS SIGHT DRAFT OR BILL OF EXCHANGE, PLEASE CALL OUR L/C PAYMENT SECTION AT ###-###-#### OR ###-###-#### OR ###-###-#### OR ###-###-####.

EXHIBIT “B”

DATE:

3003 TASMAN DRIVE

SANTA CLARA, CA 95054

STANDBY LETTERS OF CREDIT

GENTLEMEN:

FOR VALUE RECEIVED, THE UNDERSIGNED BENEFICIARY HEREBY IRREVOCABLY TRANSFERS TO: