Sublease between the Registrant and CytomX Therapeutics, Inc., dated April 25, 2016

Exhibit 10.13

SUBLEASE

THIS SUBLEASE (this “Sublease”) is dated for reference purposes as of April 25, 2016, and is made by and between CytomX Therapeutics, Inc., a Delaware corporation (“Sublessor”), and Alector LLC, a Delaware limited liability company (“Sublessee”). Sublessor and Sublessee hereby agree as follows:

1. Recitals: This Sublease is made with reference to the fact that HCP Oyster Point Ill LLC, as landlord (“Master Lessor”), and Sublessor, as tenant, entered into that certain lease, dated as of December 10, 2015 (the “Master Lease”), with respect to premises consisting of approximately 76,173 rentable square feet of space, located on the third and fourth floors (the “Premises”) of a building being constructed at 151 Oyster Point Boulevard, South San Francisco, California (the “Building”). A copy of the Master Lease is attached hereto as Exhibit A.

2. Premises:

A. Subleased Premises. Sublessor hereby subleases to Sublessee, and Sublessee hereby subleases from Sublessor, a portion of the Premises consisting of approximately 15,748 rentable square feet of space (including, without limitation, a vivarium consisting of approximately 700 square feet of space) located on the third floor of the Premises (hereinafter, the “Subleased Premises”). The Subleased Premises are more particularly described on Exhibit B attached hereto. Sublessor and Sublessee acknowledge that Master Lessor has a one-time right to remeasure the Premises as described in Section 1.2 of the Master Lease. If Master Lessor exercises such right and the square footage of the Premises and/or Building are different from those set forth in the Master Lease, the square footage of the Subleased Premises and the related amounts and percentages set forth herein shall be correspondingly adjusted (including the Base Rent) as provided in Section 1.2 of the Master Lease, as incorporated herein. Sublessor and Sublessee hereby acknowledge and agree that the rentable square footage of the Subleased Premises shall not increase by more than one percent (1%) from the rentable square footage stated herein as a result of the remeasurement by Master Lessor pursuant to Section 1.2 of the Master Lease.

B. Shared Areas. In connection with its use of the Subleased Premises, and subject to Sublessor’s reasonable rules and regulations, Sublessee shall have the non-exclusive right to use (1) its pro rata share based on the square footage of the Subleased Premises to the square footage of the Premises (“Pro Rata Share”) of the portions of the first floor chemical storage area, service yard and penthouse (“Zone 2”) serving the Premises (except that Sublessee’s Pro Rata Share of Zone 2 shall be determined based on the square footage of the Subleased Premises to the square footage of the portion of the Premises located on the third floor), on the terms set forth in the Master Lease, as incorporated herein, (ii) Sublessor’s glass wash/autoclave facility adjacent to the Subleased Premises, subject to Sublessor’s reasonable scheduling requirements, and (iii) the freight elevator at the Premises.

C. Tenant Improvements. Sublessor represents and Sublessee acknowledges that Master Lessor is required to perform certain construction work in the Premises, including the Subleased Premises, pursuant to Exhibit B of the Master Lease and in accordance with those certain plans for such work in the Subleased Premises prepared by DGA dated February 22, 2016 (excluding references therein to furnishings), which plans Sublessee has reviewed and approved (the “Plans”). Sublessee shall have no right to make any changes to such plans, request any additional or different improvements in the Subleased Premises or delay Master Lessor’s completion of such work, including taking any actions that would be considered a “Tenant Delay” under the Master Lease had such actions been taken by Sublessor. Notwithstanding the foregoing, Sublessee has elected to make, and Sublessor has approved (subject to receipt of Master Lessor’s consent), the following alterations within the Subleased Premises as shown on the plans prepared by DGA dated April 8, 2016: (i) Extend wall and create new entrance for vivarium;

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(ii) enclose room 391 (equipment room), turn into Procedure room 2 and create new entrance perpendicular to new entrance into vivarium (no need to relocate ESEW); this new procedure room only requires standard power/electrical supply or leave power supply originally intended for room 391; (iii) Room 384 (Procedure room 1) will require a chemical fume hood (vented to outside) in a location proposed by DGA (collectively, the “Sublessee Changes”). Sublessee shall be responsible for performing the Sublessee Changes at its sole cost and expense, in accordance with the terms of Article 8 of the Master Lease, as incorporated herein, using DGA as the architect and Landmark Builders as the contractor, in a manner that will not interfere with or delay Master Lessor’s performance of the Tenant Improvements or delivery of the Premises. If within one (I) year following the expiration or earlier termination of this Sublease, Sublessor restores the affected areas to the configuration shown on the Plans dated February 22, 2016 using a third party contractor reasonably selected by Sublessor, Sublessee shall be responsible for reimbursing Sublessor (or paying directly to Sublessor’s contractor at Sublessor’s election) such cost to restore within thirty (30) days after delivery of an invoice from Sublessor thereof accompanied by detailed contractor invoices evidencing such cost. Sublessor shall not request or approve any changes to such plans that would materially affect the Subleased Premises without Sublessee’s consent, which shall not be unreasonably withheld. If Sublessee fails to reasonably approve or disapprove a change within five (5) days of request by Sublessor (two (2) business days if the change was requested by Master Lessor), such change shall be deemed approved by Sublessee so long as a copy of such request for approval was concurrently sent by electronic mail to the following addresses.

3. Term:

A. Term. The term (the “Term”) of this Sublease shall be for the period commencing on the later of November 1, 2016, the “Lease Commencement Date” under the Master Lease and the date the Subleased Premises are delivered to Sublessee with the Tenant Improvements (as defined in the Master Lease) therein completed with all approvals and permits from the appropriate governmental authorities required for the legal occupancy of the Subleased Premises by Sublessee obtained (the “Commencement Date”) and ending on the last day of the thirtieth (30th) month following the Commencement Date (the “Expiration Date”), unless this Sublease is sooner terminated pursuant to its terms or the Master Lease is sooner terminated pursuant to its terms.

B. Early Possession. To tie extent permitted under the Master Lease and so long as such access does not interfere with Master Lessor’s or Sublessor’s work in the Premises or the Building, Sublessor shall permit Sublessee to enter the Subleased Premises thirty (30) days prior to the Commencement Date solely for the purpose of preparing the Subleased Premises for occupancy (including performing the Sublessee Changes) and not for the purpose of conducting business therein, provided (i) Master Lessor’s consent to this Sublease has been received, (ii) Sublessee has delivered to Sublessor the Security Deposit and first month’s Base Rent as required under Paragraph 4 and (iii) Sublessee has delivered to Sublessor evidence of all insurance required under this Sublease. Such occupancy shall be subject to all of the provisions of this Sublease, except for the obligation to pay Base Rent, Direct Expenses or utilities, shall not advance the Expiration Date of this Sublease and shall be subject to the terms of Section 6 of Exhibit B of the Master Lease.

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4. Rent:

A. Base Rent. Sublessee shall pay to Sublessor as base rent for the Subleased Premises for each month during the Term the following amounts per month (“Base Rent”):

Base Rent and Additional Rent, as defined in Paragraph 4.B below, shall be paid on or before the first (1st) day of each month. If an increase in Base Rent becomes effective on a date other than the first day of a calendar month, the Base Rent for that month shall be the sum of the two applicable rates, each prorated for the portion of the month during which the rate is in effect. Base Rent and Additional Rent shall be payable without notice or demand and without any deduction, offset, or abatement, in lawful money of the Ailed States of America. Base Rent and Additional Rent shall be paid directly to Sublessor at the applicable address set forth below Sublessor’s signature to this Sublease or such other address as may be designated in writing by Sublessor.

B. Additional Rent. All monies other than Base Rent required to be paid by Sublessor under the Master Lease as to the Subleased Premises, including, without limitation, any amounts payable by Sublessor to Master Lessor as “Direct Expenses” (as defined in Section 4.2.2 of the Master Lease) and costs of utilities under Section 6.2 of the Master Lease, as incorporated herein, with respect to the Subleased Premises shall be paid by Sublessee hereunder as and when such amounts are due under the Master Lease, as incorporated herein. Sublessee shall be entitled to its Pro Rata Share of all [illegeable], if any, given by Master Lessor to Sublessor for Sublessor’s overpayment of such expenses. Sublessee shall also pay Sublessor its Pro Rata Share, within thirty (30) days of request by Sublessor, of Sublessor’s actual and reasonable cost of maintaining and operating the autoclave/glass wash facility and in performing any repairs or providing other services to the Premises that benefit the Subleased [illegeable] (such as maintenance of any systems therein but excluding any capital improvements or expenditure except to the extent amortized over their useful lives as reasonably determined by Sublessor), and shall pay the entire cost of such amounts to the extent due to the misuse or excess use or negligence, willful misconduct or violation of this Sublease by Sublessee or its agent, employee, or contractor. All such amounts shall be deemed additional rent (“Additional Rent”). Base Rent and Additional Rent hereinafter collectively shall be referred to as “Rent”. Notwithstanding anything to the contrary in the Sublease, Sublessee shall not be i:equiretto pay any Rent or perform any obligation that is required as a result of a default by Sublessor of any of its obligations under the Master Lease (except to the extent such default was due to the negligence, willfull misconduct or violation of this Sublease by Sublessee) or the misuse, negligence or willful Misconduct of arty Sublessor or its agents, contractors or invitees or the violation of law by Sublessor.

C. Payment of First Month’s Rent. Upon execution hereof by Sublessee, Sublessee shall pay to Sublessor the sum of Seventy-Two Thousand Four Hundred Forty and 80/100 Dollars ($72,440.80), which shall constitute Base Rent for the first month of the Term.

5. Security Deposit: Upon execution hereof by Sublessee, Sublessee shall deposit with Sublessor the sum of One Hundred Fifty-Three Thousand Seven Hundred Four and 88/100 Dollars ($153,704.88) (the “Security Deposit”), in cash, as security for the performance by Sublessee of the terms and conditions of this Sublease. If Sublessee fails to pay Rent or other charges due hereunder or otherwise defaults with respect to any provision of this Sublease beyond any applicable notice and cure period, then Sublessor may draw upon, use, apply or retain all or any portion of the Security Deposit for the payment of any Rent or other charge in default, for the payment of any other sum which Sublessor has become

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obligated to pay by reason of Sublessee’s default, or to compensate Sublessor for any loss or damage which Sublessor has suffered thereby. If Sublessor so uses or applies all or any portion of the Security Deposit, then Sublessee, within ten (10) days after demand therefor, shall deposit cash with Sublessor in the amount required to restore the Security Deposit to the full amount stated above. Upon the expiration of this Sublease, Sublessor shall return to Sublessee so much of the Security Deposit as has not been applied by Sublessor pursuant to this paragraph, or which is not otherwise required to cure Sublessee’s defaults.

6. Holdover: In the event that Sublessee does not surrender the Subleased Premises by the Expiration Date in accordance with the terms of this Sublease, Sublessee shall indemnify, defend, protect and hold harmless Sublessor from and against all loss and liability resulting from Sublessee’s delay in surrendering the Subleased Premises and pay Sublessor holdover rent with respect to the Subleased Premises as provided in Section 16 of the Master Lease, as incorporated herein.

7. Repairs: Sublessor shall deliver the Subleased Premises to Sublessee in the condition in which the Premises are delivered to Sublessor under the Master Lease. The parties acknowledge and agree that Sublessor has made no representations or warranties with respect to the condition of the Subleased Premises. Sublessor shall have no obligation whatsoever to make or pay the cost of any alterations, improvements or repairs to the Subleased Premises, including, without limitation, any improvement or repair required to comply with any law. Master Lessor shall be solely responsible for performance of any repairs required to be performed by Master Lessor under the terms of the Master Lease. Sublessor shall, however, upon written request by Sublessee, use Sublessor’s reasonable efforts (without requiring Sublessor to spend more than a nominal sum) to obtain Master Lessor’s performance. Sublessor shall continue to repair and maintain in good condition and working order the autoclave/glass wash facility, the security system serving the Premises and Subleased Premises and any other systems serving the Premises and the Subleased Premises in common (except for Landlord Repair Obligations). Sublessor shall further be responsible for the repair and maintenance obligations of “Tenant” under the Master Lease with respect to the Subleased Premises, except to the extent the same result from the misuse or excess use or negligence, willful misconduct or violation of this Sublease by Sublessee, and Sublessee shall reimburse Sublessor for the actual and reasonable cost thereof (except for any capital improvements except to the extent amortized over their useful lives as reasonably determined by Sublessor).

8. Assignment and Subletting. Sublessee may not assign this Sublease, sublet the Subleased Premises, transfer any interest of Sublessee therein or permit any use of the Subleased Premises by another party (collectively, “Transfer”), without the prior written consent of Sublessor and Master Lessor (to the extent required under the Master Lease); provided, however, Sublessor’s consent shall not be required for a transfer as described in the first sentence of Section 14.8 of the Master Lease, as incorporated herein. Any Transfer shall be subject to the terms of Section 14 of the Master Lease, as incorporated herein.

9. Use: Sublessee may use the Subleased Premises only for the following uses: general office, biomedical laboratory, lab scale manufacturing and research and development, and vivarium uses and other lawful uses reasonably related to or incidental to such specified uses, all consistent with first class life sciences projects in South San Francisco, California and in compliance with, and subject to, applicable laws and the terms of the Master Lease and this Sublease. Sublessee shall not use, store, transport or dispose of any Hazardous Materials (as defined in the Master Lease) in or about the Premises except as permitted pursuant to the terms and conditions of Section 5.3 of the Master Lease, as incorporated herein. Sublessee shall comply with all reasonable rules and regulations promulgated from time to time by Sublessor and Master Lessor.

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10. Delivery and Acceptance: If Sublessor fails to deliver possession of the Subleased Premises to Sublessee on or before the date set forth in Paragraph 3.A hereof for any reason whatsoever (other than the occupancy of the Subleased Premises by Sublessor or any other party by, through or under Sublessor), then this Sublease shall not be void or voidable, nor shall Sublessor be liable to Sublessee for any loss or damage; provided, however, that in such event, Rent shall abate until Sublessor delivers possession of the Subleased Premises to Sublessee. In addition, the provisions of the last two sentences of Section 2.1 of the Master Lease, as incorporated herein, shall apply (but the applicable deadline dates shall not be extended by any “Tenant Delay” under the Master Lease except to the extent caused by an act or omission by Sublessee). If the Subleased Premises are not delivered in good condition and in compliance with all laws as set forth in the last two sentences of Section 1.1.1 of the Master Lease incorporated herein, or if any of the Tenant Improvements within the Subleased Premises are not constructed by Master Lessor in accordance with the Master Lease, upon written request by Sublessee, Sublessor shall use commercially reasonable efforts to cause Master Lessor to correct the same at no cost to Sublessee (through Direct Expenses or otherwise).

11. Improvements: No alteration or improvements shall be made to the Subleased Premises, except in accordance with the Master Lease, and with the prior written consent of both Master Lessor and Sublessor. Sublessor’s consent shall not be unreasonably withheld, conditioned or delayed, but the consent of Sublessor may be withheld if Master Lessor’s consent is not obtained.

12. Insurance: Waiver of Subrogation: Sublessee shall obtain and keep in full force and effect, at Sublessee’s sole cost and expense, during the Term, the insurance required under Section 10 of the Master Lease. Sublessee shall name Master Lessor and Sublessor as additional insureds under its liability insurance policy. The release and waiver of subrogation set forth in Section 10.5 of the Master Lease, as incorporated herein, shall be binding on the parties.

13. Default; Remedies: Sublessee shall be in material default of its obligations under this Sublease if Sublessee commits any act or omission which constitutes an event of default under the Master Lease, which has not been cured after delivery of written notice and passage of any applicable grace period provided in the Master Lease as modified, if at all, by the provisions of this Sublease. In the event of any default by Sublessee, Sublessor shall have all remedies provided pursuant to Section 19.2 of the Master Lease and by applicable law.

14. Surrender: Prior to expiration of this Sublease, Sublessee shall remove all of its trade fixtures and shall surrender the Subleased Premises to Sublessor in good condition, with any Clean-up required under the Master Lease with respect to Hazardous Materials caused by Sublessee completed, reasonable wear and tear, casualty and condemnation excepted. If the Subleased Premises are not so surrendered, then Sublessee shall be liable to Sublessor for all costs incurred by Sublessor in returning the Subleased Premises to the required condition.

15. Broker: Sublessor and Sublessee each represent to the other that they have dealt with no real estate brokers, finders, agents or salesmen other than Newmark Cornish & Carey representing Sublessee and Sublessor, in connection with this transaction. Each party agrees to hold the other party harmless from and against all claims for brokerage commissions, finder’s fees or other compensation made by any other agent, broker, salesman or finder as a consequence of such party’s actions or dealings with such agent, broker, salesman, or finder. Sublessor shall pay the commissions payable by it to Newmark Cornish & Carey in connection with this Sublease pursuant to a separate agreement.

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16. Notices: Unless at least five (5) days’ prior written notice is given in the manner set forth in this paragraph, the address of each party for all purposes connected with this Sublease shall be the applicable address set forth below its signature at the end of this Sublease. All notices, demands or communications in connection with this Sublease shall be (a) personally delivered; or (b) properly addressed and (i) submitted to an overnight courier service, charges prepaid, or (ii) deposited in the mail (certified, return receipt requested, and postage prepaid). Notices shall be deemed delivered upon receipt, if personally delivered, one (I) business day after being submitted to an overnight courier service and three (3) business days after mailing, if mailed as set forth above. All notices given to Master Lessor under the Master Lease shall be considered received only when delivered in accordance with the Master Lease.

17. Miscellaneous: Sublessor has not had an inspection of the Premises performed by a Certified Access Specialist as described in California Civil Code § 1938.

18. Other Sublease Terms:

A. Incorporation By Reference. Except as set forth below, the terms and conditions of this Sublease shall include all of the terms of the Master Lease and such terms are incorporated into this Sublease as if fully set forth herein, except that: (i) each reference in such incorporated sections to “Lease” shall be deemed a reference to “Sublease”; (ii) each reference to the “Premises”, “Lease Term” and “Base Rent” shall be deemed a reference to the “Subleased Premises”, “Term” and Base Rent under this Sublease, respectively; (iii) each reference to “Landlord” and “Tenant” shall be deemed a reference to “Sublessor” and “Sublessee”, respectively, except as otherwise expressly set forth herein; (iv) with respect to work, services, repairs, restoration, insurance, indemnities (except for the indemnity by Sublessor pursuant to the second to last sentence of Section 10.1 of the Master Lease, incorporated herein), representations, warranties or the performance of any other obligation of Master Lessor under the Master Lease, the sole obligation of Sublessor shall be to request the same in writing from Master Lessor as and when requested to do so by Sublessee, and to use Sublessor’s reasonable efforts (without requiring Sublessor to spend more than a nominal sum) to obtain Master Lessor’s performance; (v) with respect to any obligation of Sublessee to be performed under this Sublease, wherever the Master Lease grants to Sublessor a specified number of days to perform its obligations under the Master Lease, except as otherwise provided herein, Sublessee shall have three (3) fewer days to perform the obligation, including, without limitation, curing any defaults, or one-half the time period permitted under the Master Lease (rounding up for partial days), which ever allows Sublessee the greater amount of time; (vi) with respect to any approval required to be obtained from the “Landlord” under the Master Lease, such consent must be obtained from both Master Lessor and Sublessor, and the approval of Sublessor may be withheld if Master Lessor’s consent is not obtained; (vii) in any case where the “Landlord” reserves or is granted the right to manage, supervise, control, repair, alter, regulate the use of, enter or use the Premises or any areas beneath, above or adjacent thereto, perform any actions or cure any failures, such reservation or right shall be deemed to be for the benefit of both Master Lessor and Sublessor; (viii) in any case where “Tenant” is to indemnify, release or waive claims against “Landlord”, such indemnity, release or waiver shall be deemed to run from Sublessee to both Master Lessor and Sublessor; (ix) in any case where “Tenant” is to execute and deliver certain documents or notices to “Landlord”, such obligation shall be deemed to run from Sublessee to both Master Lessor and Sublessor, (x) all payments shall be made to Sublessor; and (xi) Sublessee shall pay all consent and review fees set forth in the Master Lease (with respect to a further subsubleasing of the Subleased Premises, an assignment of the Sublease or alterations constructed by Sublessee) to both Master Lessor and Sublessor and any caps shall apply separately to Master Lessor and Sublessor.

Notwithstanding the foregoing, (a) the following provisions of the Master Lease shall not be incorporated herein: Summary of Basic Lease Information, Sections 1.1.1 (the first two sentences), 1.1.2 (the first sentence), 1.3, 2.1 (the first sentence), 2.2, 4.1.2, 4.6, 5.3.1.4.3 (except with respect to the indemnity for Hazardous Materials Released by Sublessor and the nonliability provisions with respect to Hazardous Materials that exist in, on or about the Project as of the date hereof or Hazardous Materials

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Released by Master Lessor or any “Landlord Parties” under the Master Lease), 6.2 (the last sentence), 7.3, 8.5 (the last two sentences), 18 (first and third sentences), 21, 23.1 (subpart (iv) and the second to last sentence), 29.18 and 29.24 and Exhibits B (except Section 9, as to which Sublessee may only use its Pro Rata Share as designated by Sublessor) and F-H; (b) references in the following provisions to “Landlord” shall mean Master Lessor only: Sections 1.1.1 (the last two sentences, except the second reference), 1.1.2(iv), 1.1.3, 1.2 (except the last sentence), 2.1 (the last sentence), 4.2.4, 4.3, 6.1 (the first sentence), 6.5 (the first two sentences), 6.6 (the first two sentences), 7.2, 8.4 (the last reference in the first sentence), 10.2, 10.7 (the first reference), 10. 7. 2 (the last sentence), 11.1 (the second and third sentences), 11.2 (except the last reference), 13 (the first sentence), 23.1 (subpart (1) and the last sentence), 29.13 (the first sentence), 29.26 (the first sentence) and 29.29.1; (c) references in the following provisions to “Landlord” shall mean Master Lessor and Sublessor: Sections 4.5, 5.3.1.2-4, 5.3.2, 6.4, 10.4, 17, 24 (the third sentence) and 26.2; (d) the last two (2) references to “Landlord” in the second sentence of Section 10.1 of the Master Lease shall mean Master Lessor or Sublessor; (d) references to the “Permitted Use” shall mean the use permitted under Section 9 above; (e) the number of parking spaces in Section 9 of the Summary of Basic Lease Information (as referenced in Section 28 of the Master Lease) shall be 42; (f) Tenant’s Share shall mean 10.74% as to the Building and 20.67% as to the Premises; (g) subject to Master Lessor’s approval, Sublessor agrees that Alector and Alector LLC are not Objectionable Names; (h) in Section 14.3, Sublessee shall pay Sublessor the entire premium payable to Master Lessor under the Master Lease, plus fifty percent (50%) of any remaining Transfer Premium; and (i) in Section 8.1, the reference in the second sentence to $50,000 shall be to $10,000.

B. Assumption of Obligations. This Sublease is and at all times shall be subject and subordinate to the Master Lease and the rights of Master Lessor thereunder. Sublessee hereby expressly assumes and agrees: (i) to comply with all provisions of the Master Lease which are incorporated hereunder; and (ii) to perform all the obligations on the part of the “Tenant” to be performed under the terms of the Master Lease during the Term of this Sublease which are incorporated hereunder. In the event the Master Lease is terminated for any reason whatsoever, this Sublease shall terminate simultaneously with such termination without any liability of Sublessor to Sublessee. Notwithstanding the foregoing, Sublessor shall not, without Sublessee’s prior written consent, terminate the Master Lease (except as set forth in Paragraph 20 below or if Master Lessor agrees to allow Sublessee to continue to occupy the Subleased Premises for the remaining Term on the terms of this Sublease), commit any acts that would entitle Master Lessor to terminate the Master Lease, or amend or waive any provisions of the Master Lease or make any elections, exercise any right or remedy or give any consent or approval under the Master Lease in each case that would adversely affect Sublessee’s use or occupancy of the Subleased Premises or increase Sublessee’s liability hereunder. In the event of a conflict between the provisions of this Sublease and the Master Lease, as between Sublessor and Sublessee, the provisions of this Sublease shall control. In the event of a conflict between the express provisions of this Sublease and the provisions of the Master Lease, as incorporated herein, the express provisions of this Sublease shall prevail.

19. Conditions Precedent: This Sublease and Sublessor’s and Sublessee’s obligations hereunder are conditioned upon the written consent of Master Lessor. Unless waived by Sublessee and, as to subpart (iv), Sublessor in writing (which waiver shall be deemed to have been made upon Sublessee’s and Sublessor’s execution of Master Lessor’s consent form), such consent shall provide that (i) Sublessee shall be permitted to use the Hazardous Materials specifically listed on the Environmental Questionnaire completed by Sublessee as attached hereto as Exhibit D (as the same may be updated from time to time as permitted in Section 5.3 of the Master Lease), (ii) the terms of Section 10.5 of the Master Lease (Mutual Waiver of Subrogation) shall also apply as between Master Lessor and Sublessee, (iii) the terms of Section 14.8 of the Master Lease shall also apply to Sublessee such that an assignment or subletting of the Subleased Premises to a Permitted Transferee of Sublessee shall not be deemed a Transfer under the Master Lease so long as the conditions set forth in Section 14.8 of the Master Lease, as incorporated herein, are satisfied, (iv) Master Lessor approves of the Sublessee Changes pursuant to Paragraph 2.C of

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this Sublease and the restoration of such Sublessee Changes to the configuration shown in the February 22, 2016 Plans, and (v) without reducing or diminishing the signage rights of Sublessor under the Master Lease, Sublessee shall have the signage rights described in Section 23.1(i)-(iii) of the Master Lease. If Sublessor fails to obtain Master Lessor’s consent within thirty (30) days after execution of this Sublease by Sublessor, then Sublessor or Sublessee may terminate this Sublease by giving the other party written notice thereof, and Sublessor shall return to Sublessee its payment of the first month’s Rent paid by Sublessee pursuant to Paragraph 4 hereof and the Security Deposit. Sublessor shall pay all consent and review fees set forth in the Master Lease for Master Lessor’s consent to the subletting hereunder.

20. Termination; Recapture: Notwithstanding anything to the contrary herein, Sublessee acknowledges that, under the Master Lease, both Master Lessor and Sublessor have certain termination and recapture rights, including, without limitation, in Sections 11, 13 and 14. Nothing herein shall prohibit Master Lessor or Sublessor from exercising any such rights and neither Master Lessor nor Sublessor shall have any liability to Sublessee as a result thereof. In the event Master Lessor or Sublessor exercise any such termination or recapture rights, this Sublease shall terminate without any liability to Master Lessor or Sublessor.

21. Parking, and Signage. Sublessee shall have the right to park in 40 parking spaces in the on-site parking lot and garage that serves the Building as provided in Section 28 of the Master Lease, as incorporated herein. Subject to Master Lessor’s and Sublessor’s consent (with Sublessor’s consent not to be unreasonably withheld, conditioned or delayed), and provided the same do not reduce or diminish Sublessor’s ability to install its own signs, Sublessee shall have the signage rights described in Section 23.1(i)-(iii) of the Master Lease, as incorporated herein.

22. Furniture, Fixtures and Equipment: Sublessee shall have the right to use during the Term the furnishings within the Subleased Premises which will be similar to those that Sublessor acquires for the balance of the Premises in the quantities shown on Exhibit C attached hereto (the “Furniture”) at no additional cost to Sublessee. The Furniture is provided in its “AS IS, WHERE IS” condition, without representation or warranty whatsoever. Sublessee shall insure the Furniture under the property insurance policy required under the Master Lease, as incorporated herein, and pay all taxes with respect to the Furniture. Sublessee shall maintain the Furniture in good condition and repair, reasonable wear and tear excepted, and shall be responsible for any loss or damage to the same occurring during the Term. Sublessee shall surrender the Furniture to Sublessor upon the termination of this Sublease in the same condition as exists as of the Commencement Date, reasonable wear and tear excepted. Sublessee shall not remove any of the Furniture from the Subleased Premises.

23. HVAC and Janitorial: Sublessee acknowledges that HVAC service is not separately zoned to the Subleased Premises. Subject to Section 6.3 of the Master Lease, as incorporated herein, HVAC shall be provided (a) to the vivarium on a 24/7 basis and to the remainder of the Subleased Premises during normal business hours as reasonably determined by Sublessor, at levels reasonably determined by Sublessor to be normal for vivarium use in the vivarium and for office or laboratory use, as applicable, in the office and laboratory areas, and (b) at Sublessee’s sole cost and upon reasonable advance notice to Sublessor, at such other times as Sublessee may request. Sublessee acknowledges that HVAC service outside of normal business hours it requests may include service to portions of the Premises outside the Subleased Premises and Sublessee shall be responsible for the full cost of all such service. Sublessor shall provide janitorial services to the Premises (including, without limitation, the Subleased Premises) as required under Section 6.1 of the Master Lease (at least five nights per week), and Sublessee shall pay to Sublessor as Additional Rent Sublessee’s Pro Rata Share of the cost thereof in accordance with Paragraph 4.B above.

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24. Sublessor Representations: Sublessor represents and warrants that (a) the Master Lease is in full force and effect, and there exists under the Master Lease no default beyond applicable notice and cure periods by either Sublessor, or to Sublessor’s knowledge, Master Lessor, nor, to Sublessor’s knowledge, has there occurred any event which, with the giving of notice or passage of time or both, could constitute such a default, and (b) the copy of the Master Lease attached hereto as Exhibit A is a true, correct and complete copy of the Master Lease.

25. Access: Sublessee shall have access to the Subleased Premises twenty-four (24) hours a day, seven (7) days a week to the extent Sublessor is permitted such access under the Master Lease to the Premises.

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IN WITNESS WHEREOF, the parties have executed this Sublease as of the day and year first above written.

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EXHIBIT A

MASTER LEASE

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EXHIBIT B

SUBLEASED PREMISES

[Schematic]

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EXHIBIT C

FURNITURE

[List of Sub-tenant Furnishings]

EXHIBIT D

ENVIRONMENTAL QUESTIONNAIRE

[ENVIRONMENTAL QUESTIONNAIRE

FOR COMMERCIAL AND INDUSTRIAL PROPERTIES]

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LEASE

THE COVE AT OYSTER POINT

HCP OYSTER POINT III LLC,

a Delaware limited liability company

as Landlord,

and

CYTOMAX THERAPEUTICS, INC.,

a Delaware corporation,

as Tenant.

TABLE OF CONTENTS

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INDEX

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THE COVE AT OYSTER POINT

LEASE

This Lease (the “Lease”), dated as of the date set forth in Section 1 of the Summary of Basic Lease Information (the “Summary”), below, is made by and between HCP OYSTER POINT III LLC, a Delaware limited liability company (“Landlord”), and CYTOMX THERAPEUTICS, INC., a Delaware corporation (“Tenant”).

SUMMARY OF BASIC LEASE INFORMATION

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*Note that for the first Lease Year of the Lease Term, Tenant’s Base Rent obligation has been calculated as if the Premises contained only 55,000 rentable square feet. Such calculation shall not affect Tenant’s right to use the entire Premises, or Tenant’s obligations under this Lease with respect to the entire Premises, including without limitation, Tenant’s obligation to pay Tenant’s Share of Direct Expenses with respect to the Premises which shall be as provided in Section 6 of this Summary, all in accordance with the terms and conditions of this Lease.

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1. PREMISES, BUILDING, PROJECT, AND COMMON AREAS.

1.1 Premises, Building, Project and Common Areas.

1.1.1 The Premises. Landlord hereby leases to Tenant and Tenant hereby leases from Landlord the premises set forth in Section 2.2 of the Summary (the “Premises”). The outline of the Premises is set forth in Exhibit A attached hereto. The outline of the “Building” and the “Project,” as those terms are defined in Section 1.1.2 below, are further depicted on the Site Plan attached hereto as Exhibit A. The parties hereto agree that the lease of the Premises is upon and subject to the terms, covenants and conditions herein set forth, and Tenant covenants as a material part of the consideration for this Lease to keep and perform each and all of such terms, covenants and conditions by it to be kept and performed. The parties hereto hereby acknowledge that the purpose of Exhibit A is to show the approximate location of the Premises only, and such Exhibit is not meant to constitute an agreement, representation or warranty as to the construction of the Premises, the precise area thereof or the specific location of the “Common Areas,” as that term is defined in Section 1.1.3, below, or the elements thereof or of the accessways to the Premises or the “Project,” as that term is defined in Section 1.1.2, below, and that the square footage of the Premises shall be as set forth in Section 2.1 of the Summary of Basic Lease Information. Except as specifically set forth in this Lease and in the Tenant Work Letter attached hereto as Exhibit B (the “Tenant Work Letter”), Landlord shall not be obligated to provide or pay for any improvement work or services related to the improvement of the Premises. Tenant also acknowledges that neither Landlord nor any agent of Landlord has made any representation or warranty regarding the condition of the Premises, the Building or the Project or with respect to the suitability of any of the foregoing for the conduct of Tenant’s business, except as specifically set forth in this Lease and the Tenant Work Letter. For purposes of Section 1938 of the California Civil Code, Landlord hereby discloses to Tenant, and Tenant hereby acknowledges, that the Building and Premises have not undergone inspection by a Certified Access Specialist (CASp). Landlord shall deliver the Premises to Tenant in good, vacant, broom clean condition, in compliance with all laws, with the roof water-tight and shall cause the plumbing, electrical systems, fire sprinkler system, lighting, and all other building systems serving the Premises in good operating condition and repair on or before the Lease Commencement Date, or such earlier date as Landlord and Tenant mutually agree. Landlord will be responsible for causing the exterior of the Building, the existing Building entrances, and all exterior Common Areas (including required striping and handicapped spaces in the parking areas) to be in compliance with ADA and parking requirements, to the extent required to allow the legal occupancy of the Premises or completion of the Tenant Improvements.

1.1.2 The Building and The Project. The Premises constitutes the space set forth in Section 2.1 of the Summary (the “Building”). The Building is part of an office/laboratory project currently known as “The Cove at Oyster Point.” The term “Project,” as used in this Lease, shall mean (i) the Building and the Common Areas, (ii) the land (which is improved with landscaping, parking facilities and other improvements) upon which the Building and the Common Areas are located, (iii) the other office/laboratory buildings located at The Cove at Oyster Point, and the land upon which such adjacent office/laboratory buildings are located, and (iv) at Landlord’s discretion, any additional real property, areas, land, buildings or other improvements added thereto outside of the Project (provided that any such additions do not increase Tenant’s obligations under this Lease).

1.1.3 Common Areas. Tenant shall have the non-exclusive right to use in common with other tenants in the Project, and subject to the rules and regulations referred to in Article 5 of this Lease, those portions of the Project which are provided, from time to time, for use in common by Landlord, Tenant and any other tenants of the Project, which shall include the shipping and receiving area in the Building (such areas, together with such other portions of the Project designated by Landlord, in its

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discretion, are collectively referred to herein as the “Common Areas”). Landlord shall maintain and operate the Common Areas, including all sprinkler and other systems serving the Common Areas, in a first class manner, and the use thereof shall be subject to such rules, regulations and restrictions as Landlord may reasonably make from time to time. Landlord reserves the right to close temporarily, make alterations or additions to, or change the location of elements of the Project and the Common Areas, provided that in connection therewith Landlord will use commercially reasonable efforts to minimize any interference with Tenant’s use of and access to the Premises and parking areas. Landlord hereby acknowledges that as of the date of this Lease Landlord is planning to construct and operate an amenities center in the Building for use by the tenants of the Project during the Lease Term, and in connection therewith Landlord agrees to utilize commercially reasonable efforts to operate and maintain such amenities center (which amenities center shall include a café) throughout the Lease Term (provided that Tenant acknowledges that the amenities center is currently anticipated to begin operations after the Lease Commencement Date); provided, however, Tenant nevertheless acknowledges herby that if despite such commercially reasonable efforts Landlord is unable for any reason to maintain continuous operation of the amenities center during the Lease Term, in no event shall such failure be deemed a default of the Lease, nor shall such failure impact the validity of this Lease and Landlord shall not be subject to any liability for such failure, provided that in such event Landlord shall utilize commercially reasonable efforts to provide replacement food services to Tenant (e.g., an on-site café in a different location or the routine scheduling of food trucks to the Project).

1.2 Rentable Square Feet of Premises. Tenant hereby acknowledges and agrees that Landlord shall have the one-time right during the Lease Term to remeasure the rentable square footage of the Premises and/or Building in accordance with the terms of this Section 1.2. Any such remeasurement shall be determined in accordance with the standards set forth in ANSI Z65.1-2010, as promulgated by the Building Owners and Managers Association (the “BOMA Standard”), and subject to related guidelines applicable thereto. Landlord’s space planner/architect shall certify any such remeasurement and shall provide reasonable documentation to Tenant for Tenant’s review following such remeasurement. In the event that Landlord’s space planner/architect determines that the rentable square footage of the Premises and/or Building are different from those set forth in this Lease, all amounts, percentages and figures appearing or referred to in this Lease based upon such amounts (including, without limitation, the amount of the Base Rent, Tenant Improvement Allowance, Additional Tenant Improvement Allowance, and Tenant’s Share) shall be modified in accordance with such determination, provided that Landlord and Tenant hereby acknowledge and agree that the rentable square footage of the Premises shall not increase by more than one percent (1%) from the rentable square footage set forth in Section 2.2 of the Summary. If such determination is made, it will be confirmed in writing by Landlord to Tenant.

1.3 Right of First Offer.

1.3.1 Right of First Offer. Subject to the terms and conditions of this Section 1.3, Landlord hereby grants to Tenant an on-going right of first offer during the initial Lease Term with respect to any space on the second (2nd) floor of the Building (the “First Offer Space”). Notwithstanding the foregoing, such first offer right of Tenant shall commence only following the expiration or earlier termination of the existing leases of the First Offer Space (the “Existing Leases”) (including renewals of any such lease, irrespective of whether any such renewal is currently set forth in such lease or is subsequently granted or agreed upon, and regardless of whether such renewal is consummated pursuant to a lease amendment or a new lease). Such right of first offer shall be subordinate to all rights granted in any Existing Leases, which rights relate to the First Offer Space and are set forth in the Existing Leases upon execution thereof, including, without limitation, any renewal, expansion, first offer, first refusal, first negotiation and other rights, regardless of whether such rights are executed strictly in accordance with their respective terms or pursuant to a lease amendment or a new lease (the “Superior Rights”). Further, such right of first offer shall be subject and subordinate to the terms of any renewal right

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contained in any lease of the First Offer Space entered into by Landlord with a third party after Tenant’s failure to exercise its right of first offer as provided in this Section 1.3 (the “Intervening Leases”). All such tenants under Existing Leases or Intervening Leases, are collectively referred to as the “Superior Right Holders”.

1.3.2 Procedure for Lease.

1.3.2.1 Procedure for Offer. Subject to the terms hereof, Landlord shall notify Tenant (the “First Offer Notice”) prior to entering into any lease with a third party for the First Offer Space, which notice shall outline the base rent, allowance amounts if any, length of term, and other economic terms on which Landlord would be willing to lease the First Offer Space (as set forth in such proposal) to Tenant (the “Fundamental Terms”). Pursuant to such First Offer Notice, Landlord shall offer to lease to Tenant the applicable First Offer Space on the Fundamental Terms.

1.3.2.2 Procedure for Acceptance. If Tenant wishes to exercise Tenant’s right of first offer with respect to the First Offer Space described in the First Offer Notice, then within five (5) business days after delivery of the First Offer Notice to Tenant, Tenant shall deliver notice to Landlord of Tenant’s irrevocable exercise of its right of first offer with respect to all of the First Offer Space described in the First Offer Notice on the Fundamental Terms provided for therein. If Tenant does not so notify Landlord within such five (5) business day period of Tenant’s exercise of its first offer right, then Landlord shall be free to negotiate and enter into a lease for the First Offer Space to anyone whom it desires on any terms that Landlord desires, provided that, if Landlord has not entered into any such lease within ninety (90) days after the date of delivery of the First Offer Notice, then, prior to entering into any lease of such First Offer Space, Landlord shall first again offer such space to Tenant in accordance with the terms of this Section 1.3, provided that, prior to the entering into a lease of such space on terms that are more than 10% more favorable to the tenant than those set forth in the First Offer Notice (as determined on a net effective basis), Landlord shall first deliver any other First Officer Notice to Tenant offering such space to Tenant on such reduced terms. Tenant shall respond to any such “re-offer” within five (5) days after delivery of such “re-offer” notice.

1.3.2.3 Construction In First Offer Space. Unless the Fundamental Terms provided to Tenant for the First Offer Space otherwise specify, Tenant shall take the First Offer Space in its “as is” condition, and Landlord shall not be obligated to provide or pay for any improvement of the First Offer Space. For the avoidance of doubt, if the Fundamental Terms include a tenant improvement allowance or a turn-key build out, Tenant shall receive the same allowance or turn-key build out, as applicable.

1.3.2.4 Lease of First Offer Space. If Tenant timely exercises Tenant’s right of first offer to lease First Offer Space as set forth herein, Tenant shall within fifteen (15) days after receipt of Landlord’s first draft of an amendment accurately setting forth the Fundamental Terms and not containing any new material terms, enter an amendment to this Lease (the “First Offer Space Amendment”) for such First Offer Space pursuant to this Section 1.3. Tenant’s lease of such First Offer Space shall be upon the express terms set forth in the First Offer Notice, but otherwise upon the same general terms and conditions set forth in this Lease and this Section 1.3. The First Offer Space Lease shall not contain the rights set forth in Section 2.2, below, unless such rights were set forth in the First Offer Notice. The term of Tenant’s lease of the First Offer Space shall commence on the date set forth in the First Offer Notice (provided that such commencement date shall in no event be earlier than the date of Landlord’s delivery of the applicable First Offer Space to Tenant), and shall expire on the applicable date set forth in the First Offer Notice (the “First Offer Space Expiration Date”).

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1.3.2.5 Limitation of Exercise of First Offer Right. The right to lease First Offer Space as provided in this Section 1.3 may not be exercised if, as of the date of the attempted exercise of the expansion option by Tenant, Tenant is in default under this Lease, beyond any applicable notice and cure period. The terms of this Section 1.3 shall be personal to the originally named Tenant hereunder (the “Original Tenant”) or a Permitted Transferee, and may not be exercised by any assignee, subtenant, or other Transferee of Original Tenant’s interest in this Lease other than a Permitted Transferee. Tenant’s right of first offer shall be continuous during the initial Lease Term. Tenant’s rejection of any particular offer shall not relieve Landlord of its obligation to again offer the First Offer Space to Tenant any time the First Offer Space subsequently becomes available (provided that Tenant’s rights under this Section 1.3 shall be subject and subordinate to the renewal rights of any tenant under a lease entered into by Landlord after Tenant has declined or failed to respond to a First Offer Notice).

2. LEASE TERM; OPTION TERM.

2.1 Lease Term. The terms and provisions of this Lease shall be effective as of the date of this Lease. The term of this Lease (the “Lease Term”) shall be as set forth in Section 3.1 of the Summary, shall commence on the date set forth in Section 3.2 of the Summary (the “Lease Commencement Date”), and shall terminate on the date set forth in Section 3.3 of the Summary (the “Lease Expiration Date”) unless this Lease is sooner terminated as hereinafter provided. For purposes of this Lease, the term “Lease Year” shall mean each consecutive twelve (12) month period during the Lease Term. At any time during the Lease Term, Landlord may deliver to Tenant a notice in the form as set forth in Exhibit C, attached hereto, as a confirmation only of the information set forth therein, which Tenant shall execute and return to Landlord within five (5) days of receipt thereof. Notwithstanding the foregoing, if Landlord has not delivered possession of the Premises in the condition required by Section 1.1.1, above, (1) on or before February 1, 2017, then, as Tenant’s sole remedy for such delay, the date Tenant is otherwise obligated to commence payment of rent shall be delayed by one day for each day that the delivery date is delayed beyond such date, or (2) June 1, 2017, then, Tenant shall also have the right to terminate this Lease by written notice thereof to Landlord, whereupon any monies previously paid by Tenant to Landlord shall be reimbursed to Tenant. The foregoing dates shall be extended to the extent of any delays in delivery of possession caused by (i) Tenant Delay, as provided in Section 1(j) of the Tenant Work Letter, or (ii) war, terrorism, acts of God, natural disaster, civil unrest, governmental strike or area-wide or industry-wide labor disputes, inability to obtain services, labor, or materials or reasonable substitutes therefor, or delays due to utility companies that are not the result of any action or inaction of Landlord (provided that any such delay in this item (ii) shall not extend any such date by more than ninety (90) days).

2.2 Option Term.

2.2.1 Option Right. Landlord hereby grants to the Original Tenant, and its “Permitted Assignees”, as that term is defined in Section 14.8, below, one (1) option to extend the Lease Term for a period of five (5) years (the “Option Term”), which option shall be irrevocably exercised only by written notice delivered by Tenant to Landlord not more than fifteen (15) months nor less than nine (9) months prior to the expiration of the initial Lease Term, provided that the following conditions (the “Option Conditions”) are satisfied: (i) as of the date of delivery of such notice, Tenant is not in default under this Lease, after the expiration of any applicable notice and cure period; (ii) Tenant has not previously been in default under this Lease, after the expiration of any applicable notice and cure period, more than twice in the twelve (12) month period prior to the date of Tenant’s attempted exercise; and (iii) the Lease then remains in full force and effect. Landlord may, at Landlord’s option, exercised in Landlord’s sole and absolute discretion, waive any of the Option Conditions in which case the option, if otherwise properly exercised by Tenant, shall remain in full force and effect. Upon the proper exercise of such option to extend, and provided that Tenant satisfies all of the Option Conditions (except those, if any, which are

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waived by Landlord), the Lease Term, as it applies to the Premises, shall be extended for a period of five (5) years. The rights contained in this Section 2.2 shall be personal to Original Tenant and any Permitted Assignees, and may be exercised by Original Tenant or such Permitted Assignees (and not by any assignee, sublessee or other “Transferee,” as that term is defined in Section 14.1 of this Lease, of Tenant’s interest in this Lease).

2.2.2 Option Rent. The annual Rent payable by Tenant during the Option Term (the “Option Rent”) shall be equal to the “Fair Rental Value,” as that term is defined below, for the Premises as of the commencement date of the Option Term. The “Fair Rental Value,” as used in this Lease, shall be equal to the annual rent per rentable square foot (including additional rent and considering any “base year” or “expense stop” applicable thereto), including all escalations, at which tenants (pursuant to leases consummated within the twelve (12) month period preceding the first day of the Option Term), are leasing non-sublease, non-encumbered, non-equity space which is not significantly greater or smaller in size than the subject space, with a comparable level of improvements (excluding any property that Tenant would be allowed to remove from the Premises at the termination of the Lease), for a comparable lease term, in an arm’s length transaction, which comparable space is located in the “Comparable Buildings,” as that term is defined in this Section 2.2.2, below (transactions satisfying the foregoing criteria shall be known as the “Comparable Transactions”), taking into consideration the following concessions (the “Concessions”): (a) rental abatement concessions, if any, being granted such tenants in connection with such comparable space; (b) tenant improvements or allowances provided or to be provided for such comparable space, and taking into account the value, if any, of the existing improvements in the subject space, such value to be based upon the age, condition, design, quality of finishes and layout of the improvements and the extent to which the same can be utilized by a general office/lab user other than Tenant; and (c) other reasonable monetary concessions being granted such tenants in connection with such comparable space; provided, however, that in calculating the Fair Rental Value, no consideration shall be given to the fact that Landlord is or is not required to pay a real estate brokerage commission in connection with Tenant’s exercise of its right to extend the Lease Term, or the fact that landlords are or are not paying real estate brokerage commissions in connection with such comparable space. The Concessions shall be reflected in the effective rental rate (which effective rental rate shall take into consideration the total dollar value of such Concessions as amortized on a straight-line basis over the applicable term of the Comparable Transaction (in which case such Concessions evidenced in the effective rental rate shall not be granted to Tenant)) payable by Tenant. The term “Comparable Buildings” shall mean the Building and those other life sciences buildings which are comparable to the Building in terms of age (based upon the date of completion of construction or major renovation of to the building), quality of construction, level of services and amenities, size and appearance, and are located in South San Francisco, California and the surrounding commercial area.

2.2.3 Determination of Option Rent. In the event Tenant timely and appropriately exercises an option to extend the Lease Term, Landlord shall notify Tenant of Landlord’s determination of the Option Rent within thirty (30) days thereafter. If Tenant, on or before the date which is ten (10) days following the date upon which Tenant receives Landlord’s determination of the Option Rent, in good faith objects to Landlord’s determination of the Option Rent, then Landlord and Tenant shall attempt to agree upon the Option Rent using their best good-faith efforts. If Landlord and Tenant fail to reach agreement within ten (10) days following Tenant’s objection to the Option Rent (the “Outside Agreement Date”), then Tenant shall have the right to withdraw its exercise of the option by delivering written notice thereof to Landlord within five (5) days thereafter, in which event Tenant’s right to extend the Lease pursuant to this Section 2.2 shall be of no further force or effect. If Tenant does not withdraw its exercise of the extension option, each party shall make a separate determination of the Option Rent, as the case may be, within ten (10) days after the Outside Agreement Date, and such determinations shall be submitted to arbitration in accordance with Sections 2.2.3.1 through 2.2.3.7, below. If Tenant fails to object to Landlord’s determination of the Option Rent within the time period set forth herein, then Tenant shall be deemed to have objected to Landlord’s determination of Option Rent.

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2.2.3.1 Landlord and Tenant shall each appoint one arbitrator who shall be a real estate appraiser who shall have been active over the five (5) year period ending on the date of such appointment in the appraisal of other class A life sciences buildings located in the South San Francisco market area. The determination of the arbitrators shall be limited solely to the issue of whether Landlord’s or Tenant’s submitted Option Rent is the closest to the actual Option Rent, taking into account the requirements of Section 2.2.2 of this Lease, as determined by the arbitrators. Each such arbitrator shall be appointed within fifteen (15) days after the Outside Agreement Date. Landlord and Tenant may consult with their selected arbitrators prior to appointment and may select an arbitrator who is favorable to their respective positions. The arbitrators so selected by Landlord and Tenant shall be deemed “Advocate Arbitrators.”

2.2.3.2 The two (2) Advocate Arbitrators so appointed shall be specifically required pursuant to an engagement letter within ten (10) days of the date of the appointment of the last appointed Advocate Arbitrator to agree upon and appoint a third arbitrator (“Neutral Arbitrator”) who shall be qualified under the same criteria set forth hereinabove for qualification of the two Advocate Arbitrators, except that neither the Landlord or Tenant or either parties’ Advocate Arbitrator may, directly or indirectly, consult with the Neutral Arbitrator prior or subsequent to his or her appearance. The Neutral Arbitrator shall be retained via an engagement letter jointly prepared by Landlord’s counsel and Tenant’s counsel.

2.2.3.3 The three arbitrators shall, within thirty (30) days of the appointment of the Neutral Arbitrator, reach a decision as to whether the parties shall use Landlord’s or Tenant’s submitted Option Rent, and shall notify Landlord and Tenant thereof.

2.2.3.4 The decision of the majority of the three arbitrators shall be binding upon Landlord and Tenant.

2.2.3.5 If either Landlord or Tenant fails to appoint an Advocate Arbitrator within fifteen (15) days after the Outside Agreement Date, then either party may petition the presiding judge of the Superior Court of San Mateo County to appoint such Advocate Arbitrator subject to the criteria in Section 2.2.3.1 of this Lease, or if he or she refuses to act, either party may petition any judge having jurisdiction over the parties to appoint such Advocate Arbitrator.

2.2.3.6 If the two (2) Advocate Arbitrators fail to agree upon and appoint the Neutral Arbitrator, then either party may petition the presiding judge of the Superior Court of San Mateo County to appoint the Neutral Arbitrator, subject to criteria in Section 2.2.3.1 of this Lease, or if he or she refuses to act, either party may petition any judge having jurisdiction over the parties to appoint such arbitrator.

2.2.3.7 The cost of the arbitration shall be paid by Landlord and Tenant equally.

2.2.3.8 In the event that the Option Rent shall not have been determined pursuant to the terms hereof prior to the commencement of the Option Term, Tenant shall be required to pay the Option Rent initially provided by Landlord to Tenant, and upon the final determination of the Option Rent, the payments made by Tenant shall be reconciled with the actual amounts of Option Rent due, and the appropriate party shall make any corresponding payment to the other party.

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3. BASE RENT. Tenant shall pay, without prior notice or demand, to Landlord at the address set forth in Section 4 of the Summary, or, at Landlord’s option, at such other place as Landlord may from time to time designate in writing, by a check for currency which, at the time of payment, is legal tender for private or public debts in the United States of America, base rent (“Base Rent”) as set forth in Section 4 of the Summary, payable in equal monthly installments as set forth in Section 4 of the Summary in advance on or before the first day of each and every calendar month during the Lease Term, without any setoff or deduction whatsoever. The Base Rent for the first full month of the Lease Term shall be paid at the time of Tenant’s execution of this Lease. If any Rent payment date (including the Lease Commencement Date) falls on a day of the month other than the first day of such month or if any payment of Rent is for a period which is shorter than one month, the Rent for any fractional month shall accrue on a daily basis for the period from the date such payment is due to the end of such calendar month or to the end of the Lease Term at a rate per day which is equal to 1/365 of the applicable annual Rent. All other payments or adjustments required to be made under the terms of this Lease that require proration on a time basis shall be prorated on the same basis.

4. ADDITIONAL RENT.

4.1 General Terms.

4.1.1 Direct Expenses; Additional Rent. In addition to paying the Base Rent specified in Article 3 of this Lease, Tenant shall pay “Tenant’s Share” of the annual “Direct Expenses,” as those terms are defined in Sections 4.2.6 and 4.2.2 of this Lease, respectively, allocable to the Building as described in Section 4.3. Such payments by Tenant, together with any and all other amounts payable by Tenant to Landlord pursuant to the terms of this Lease, are hereinafter collectively referred to as the “Additional Rent”, and the Base Rent and the Additional Rent are herein collectively referred to as “Rent.” All amounts due under this Article 4 as Additional Rent shall be payable for the same periods and in the same manner as the Base Rent. Without limitation on other obligations of Tenant which survive the expiration of the Lease Term, the obligations of Tenant to pay the Additional Rent provided for in this Article 4 shall survive the expiration of the Lease Term.

4.1.2 Triple Net Lease. Landlord and Tenant acknowledge that, to the extent provided in this Lease, it is their intent and agreement that this Lease be a “TRIPLE NET” lease and that as such, the provisions contained in this Lease are intended to pass on to Tenant or reimburse Landlord for the costs and expenses reasonably associated with this Lease, the Building and the Project, and Tenant’s operation therefrom to the extent provided in this Lease. To the extent such costs and expenses payable by Tenant cannot be charged directly to, and paid by, Tenant, such costs and expenses shall be paid by Landlord but reimbursed by Tenant as Additional Rent.

4.2 Definitions of Key Terms Relating to Additional Rent. As used in this Article 4, the following terms shall have the meanings hereinafter set forth:

4.2.1 Intentionally Deleted.

4.2.2 ”Direct Expenses” shall mean “Operating Expenses” and “Tax Expenses.”

4.2.3 ”Expense Year” shall mean each calendar year in which any portion of the Lease Term falls, through and including the calendar year in which the Lease Term expires, provided that Landlord, upon notice to Tenant, may change the Expense Year from time to time to any other twelve (12) consecutive month period, and, in the event of any such change, Tenant’s Share of Direct Expenses shall be equitably adjusted for any Expense Year involved in any such change.

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4.2.4 ”Operating Expenses” shall mean all expenses, costs and amounts of every kind and nature which Landlord pays or accrues during any Expense Year because of or in connection with the ownership, management, maintenance, security, repair, replacement, restoration or operation of the Project, or any portion thereof. Without limiting the generality of the foregoing, Operating Expenses shall specifically include any and all of the following: (i) the cost of supplying all utilities, the cost of operating, repairing and maintaining the utility, telephone, mechanical, sanitary, storm drainage, and elevator systems, and the cost of maintenance and service contracts in connection therewith; (ii) the cost of licenses, certificates, permits and inspections and the cost of contesting any governmental enactments which are reasonably likely to increase Operating Expenses during the Lease Term, and the costs incurred in connection with a governmentally mandated transportation system management program or similar program; (iii) the cost of all insurance carried by Landlord in connection with the Project and Premises as reasonably determined by Landlord; (iv) the cost of landscaping, relamping, and all supplies, tools, equipment and materials used in the operation, repair and maintenance of the Project, or any portion thereof; (v) the cost of parking area operation, repair, restoration, and maintenance; (vi) management and/or incentive fees, consulting fees, legal fees and accounting fees, of all contractors and consultants in connection with the management, operation, maintenance and repair of the Project; (vii) payments under any equipment rental agreements; (viii) subject to item (f), below, wages, salaries and other compensation and benefits, including taxes levied thereon, of all persons engaged in the operation, maintenance and security of the Project; (ix) costs under any easement pertaining to the sharing of costs by the Project; (x) operation, repair, maintenance and replacement of all systems and equipment and components thereof of the Project; (xi) the cost of janitorial, alarm, security and other services, replacement of wall and floor coverings, ceiling tiles and fixtures in Common Areas, maintenance and replacement of curbs and walkways, repair to roofs and re-roofing; (xii) amortization (including interest on the unamortized cost) over such period of time as Landlord shall reasonably determine, of the cost of acquiring or the rental expense of personal property used in the maintenance, operation and repair of the Project, or any portion thereof; (xiii) the cost of capital improvements or other costs incurred in connection with the Project (A) which are intended to effect economies in the operation or maintenance of the Project, or any portion thereof, or to reduce current or future Operating Expenses or to enhance the safety or security of the Project or its occupants, (B) which are required to comply with present or anticipated conservation programs, (C) which are replacements or modifications of nonstructural items located in the Common Areas required to keep the Common Areas in good order or condition, or (D) which are required under any governmental law or regulation; provided, however, that any capital expenditure shall be amortized (including reasonable interest on the amortized cost) over the reasonable useful life of such capital item; and (xiv) costs, fees, charges or assessments imposed by, or resulting from any mandate imposed on Landlord by, any federal, state or local government for fire and police protection, trash removal, community services, or other services which do not constitute “Tax Expenses” as that term is defined in Section 4.2.5, below, and (xv) payments under any easement, license, operating agreement, declaration, restrictive covenant, or instrument pertaining to the sharing of costs by the Building, including, without limitation, any covenants, conditions and restrictions affecting the property, and reciprocal easement agreements affecting the property, any parking licenses, and any agreements with transit agencies affecting the Property (collectively, “Underlying Documents”). Notwithstanding the foregoing, for purposes of this Lease, Operating Expenses shall not, however, include:

(a) costs, including legal fees, space planners’ fees, advertising and promotional expenses (except as otherwise set forth above), and brokerage fees incurred in connection with the original construction or development, or original or future leasing of the Project, and costs, including permit, license and inspection costs, incurred with respect to the installation of tenant improvements made for new tenants initially occupying space in the Project after the Lease Commencement Date or incurred in renovating or otherwise improving, decorating, painting or redecorating vacant space for tenants or other occupants of the Project (excluding, however, such costs relating to any common areas of the Project or parking facilities);

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(b) except as set forth in items (xii), (xiii), and (xiv) above, depreciation, interest and principal payments on mortgages and other debt costs, if any, penalties and interest;

(c) costs for which the Landlord is reimbursed by any tenant or occupant of the Project or by insurance by its carrier or any tenant’s carrier or by anyone else, electric power costs for which any tenant directly contracts with the local public service company and costs of utilities and services provided to other tenants that are not provided to Tenant;

(d) any bad debt loss, rent loss, or reserves for bad debts or rent loss or other reserves to the extent not used in the same year;

(e) costs associated with the operation of the business of the partnership or entity which constitutes the Landlord, as the same are distinguished from the costs of operation of the Project (which shall specifically include, but not be limited to, accounting costs associated with the operation of the Project). Costs associated with the operation of the business of the partnership or entity which constitutes the Landlord include costs of partnership accounting and legal matters, costs of defending any lawsuits with any mortgagee (except as the actions of the Tenant may be in issue), costs of selling, syndicating, financing, mortgaging or hypothecating any of the Landlord’s interest in the Project, and costs incurred in connection with any disputes between Landlord and its employees, between Landlord and Project management, or between Landlord and other tenants or occupants;

(f) the wages and benefits of any employee who does not devote substantially all of his or her employed time to the Project unless such wages and benefits are prorated to reflect time spent on operating and managing the Project vis-a-vis time spent on matters unrelated to operating and managing the Project; provided, that in no event shall Operating Expenses for purposes of this Lease include wages and/or benefits attributable to personnel above the level of Project manager;

(g) amount paid as ground rental for the Project by the Landlord;

(h) except for a property management fee not to exceed three percent (3%) of gross revenues, overhead and profit increment paid to the Landlord, and any amounts paid to the Landlord or to subsidiaries or affiliates of the Landlord for services in the Project to the extent the same exceeds the costs of such services rendered by qualified, first-class unaffiliated third parties on a competitive basis;

(i) any compensation paid to clerks, attendants or other persons in commercial concessions operated by the Landlord (other than as direct reimbursement for costs which, if incurred directly by Landlord, would properly be included in Operating Expenses);

(j) rentals and other related expenses incurred in leasing air conditioning systems, elevators or other equipment which if purchased the cost of which would be excluded from Operating Expenses as a capital cost, except equipment not affixed to the Project which is used in providing engineering, janitorial or similar services and, further excepting from this exclusion such equipment rented or leased to remedy or ameliorate an emergency condition in the Project;

(k) all items and services for which Tenant or any other tenant in the Project reimburses Landlord or which Landlord provides selectively to one or more tenants (other than Tenant) without reimbursement;

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(l) any costs expressly excluded from Operating Expenses elsewhere in this Lease;

(m) rent for any office space occupied by Project management personnel;

(n) costs arising from the gross negligence or willful misconduct of Landlord or its agents, employees or contractors in connection with this Lease;

(o) costs incurred to comply with laws relating to the removal or remediation of hazardous material (as defined under applicable law), and any costs of fines or penalties relating to the presence of hazardous material, in each case to the extent not brought into the Building or Premises by Tenant or any Tenant Parties;

(p) costs to correct any construction defect in the Project or to remedy any violation of a covenant, condition, restriction, underwriter’s requirement or law that exists as of the Lease Commencement Date;

(q) capital costs occasioned by casualties or condemnation.

(r) legal fees, accountants’ fees (other than normal bookkeeping expenses) and other expenses incurred in connection with disputes of tenants or other occupants of the Project or associated with the enforcement of the terms of any leases with tenants or the defense of Landlord’s title to or interest in the Project or any part thereof;

(s) costs incurred due to a violation by Landlord or any other tenant of the Project of the terms and conditions of a lease; and

(t) self-insurance retentions

4.2.5 Taxes.

4.2.5.1 ”Tax Expenses” shall mean all federal, state, county, or local governmental or municipal taxes, fees, charges or other impositions of every kind and nature, whether general, special, ordinary or extraordinary (including, without limitation, real estate taxes, general and special assessments, transit taxes, leasehold taxes or taxes based upon the receipt of rent, including gross receipts or sales taxes applicable to the receipt of rent, unless required to be paid by Tenant, personal property taxes imposed upon the fixtures, machinery, equipment, apparatus, systems and equipment, appurtenances, furniture and other personal property used in connection with the Project, or any portion thereof), which shall be paid or accrued during any Expense Year (without regard to any different fiscal year used by such governmental or municipal authority) because of or in connection with the ownership, leasing and operation of the Project, or any portion thereof.

4.2.5.2 Tax Expenses shall include, without limitation: (i) Any tax on the rent, right to rent or other income from the Project, or any portion thereof, or as against the business of leasing the Project, or any portion thereof; (ii) Any assessment, tax, fee, levy or charge in addition to, or in substitution, partially or totally, of any assessment, tax, fee, levy or charge previously included within the definition of real property tax; (iii) Any assessment, tax, fee, levy, or charge allocable to or measured by the area of the Premises or the Rent payable hereunder, including, without limitation, any business or gross income tax or excise tax with respect to the receipt of such rent, or upon or with respect to the possession, leasing, operating, management, maintenance, alteration, repair, use or occupancy by Tenant of the Premises, or any portion thereof; and (iv) Any assessment, tax, fee, levy or charge, upon this transaction or any document to which Tenant is a party, creating or transferring an interest or an estate in the Premises or the improvements thereon.

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4.2.5.3 Any costs and expenses (including, without limitation, reasonable attorneys’ and consultants’ fees) incurred in attempting to protest, reduce or minimize Tax Expenses shall be included in Tax Expenses in the Expense Year such expenses are incurred. Tax refunds shall be credited against Tax Expenses and refunded to Tenant regardless of when received, based on the Expense Year to which the refund is applicable, provided that in no event shall the amount to be refunded to Tenant for any such Expense Year exceed the total amount paid by Tenant as Additional Rent under this Article 4 for such Expense Year. If Tax Expenses for any period during the Lease Term or any extension thereof are increased after payment thereof for any reason, including, without limitation, error or reassessment by applicable governmental or municipal authorities, Tenant shall pay Landlord upon demand Tenant’s Share of any such increased Tax Expenses. Notwithstanding anything to the contrary contained in this Section 4.2.5, there shall be excluded from Tax Expenses (i) all excess profits taxes, franchise taxes, gift taxes, capital stock taxes, inheritance and succession taxes, transfer taxes, estate taxes, federal and state income taxes, and other taxes to the extent applicable to Landlord’s net income (as opposed to rents, receipts or income attributable to operations at the Project), (ii) any items included as Operating Expenses, (iii) any items paid by Tenant under Section 4.5 of this Lease, (iv) assessments in excess of the amount which would be payable if such assessment expense were paid in installments over the longest permitted term; (v) taxes imposed on land and improvements other than the Project; and (vi) tax increases resulting from the improvement of any of the Project for the sole use of other occupants.

4.2.6 “Tenant’s Share” shall mean the percentage set forth in Section 6 of the Summary.

4.3 Allocation of Direct Expenses. The parties acknowledge that the Building is a part of a multi-building project and that the costs and expenses incurred in connection with the Project (i.e., the Direct Expenses) should be shared between the Building and the other buildings in the Project. Accordingly, as set forth in Section 4.2 above, Direct Expenses (which consist of Operating Expenses and Tax Expenses) are determined annually for the Project as a whole, and a portion of the Direct Expenses, which portion shall be determined by Landlord on an equitable basis, shall be allocated to the Building (as opposed to other buildings in the Project). Such portion of Direct Expenses allocated to the Building shall include all Direct Expenses attributable solely to the Building and a pro rata portion of the Direct Expenses attributable to the Project as a whole, and shall not include Direct Expenses attributable solely to other buildings in the Project.

4.4 Calculation and Payment of Additional Rent. Commencing on the Lease Commencement Date, Tenant shall pay to Landlord, in the manner set forth in Section 4.4.1, below, and as Additional Rent, Tenant’s Share of Direct Expenses for each Expense Year during the Lease Term.

4.4.1 Statement of Actual Direct Expenses and Payment by Tenant. Landlord shall give to Tenant within five (5) months following the end of each Expense Year, a statement (the “Statement”) which shall state the Direct Expenses incurred or accrued for such preceding Expense Year, and which shall indicate the amount of Tenant’s Share of Direct Expenses. Upon receipt of the Statement for each Expense Year commencing or ending during the Lease Term, Tenant shall pay, with its next installment of Base Rent due that is at least thirty (30) days thereafter, the full amount of Tenant’s Share of Direct Expenses for such Expense Year, less the amounts, if any, paid during such Expense Year as “Estimated Direct Expenses,” as that term is defined in Section 4.4.2, below, and if Tenant paid more as Estimated Direct Expenses than the actual Tenant’s Share of Direct Expenses, Tenant shall receive a credit in the amount of Tenant’s overpayment against Rent next due under this Lease. The failure of Landlord to timely furnish the Statement for any Expense Year shall not prejudice Landlord or Tenant

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from enforcing its rights under this Article 4. Even though the Lease Term has expired and Tenant has vacated the Premises, when the final determination is made of Tenant’s Share of Direct Expenses for the Expense Year in which this Lease terminates, Tenant shall immediately pay to Landlord such amount, and if Tenant paid more as Estimated Direct Expenses than the actual Tenant’s Share of Direct Expenses, Landlord shall, within thirty (30) days, deliver a check payable to Tenant in the amount of the overpayment. The provisions of this Section 4.4.1 shall survive the expiration or earlier termination of the Lease Term. Notwithstanding the immediately preceding sentence, Tenant shall not be responsible for Tenant’s Share of any Direct Expenses attributable to any Expense Year which are first billed to Tenant more than two (2) calendar years after the earlier of the expiration of the applicable Expense Year or the Lease Expiration Date, provided that in any event Tenant shall be responsible for Tenant’s Share of Direct Expenses levied by any governmental authority or by any public utility companies at any time following the Lease Expiration Date which are attributable to any Expense Year (provided that Landlord delivers Tenant a bill for such amounts within two (2) years following Landlord’s receipt of the bill therefor).

4.4.2 Statement of Estimated Direct Expenses. In addition, Landlord shall give Tenant a yearly expense estimate statement (the “Estimate Statement”) which shall set forth Landlord’s reasonable estimate (the “Estimate”) of what the total amount of Direct Expenses for the then-current Expense Year shall be and the estimated Tenant’s Share of Direct Expenses (the “Estimated Direct Expenses”). The failure of Landlord to timely furnish the Estimate Statement for any Expense Year shall not preclude Landlord from enforcing its rights to collect any Estimated Direct Expenses under this Article 4, nor shall Landlord be prohibited from revising any Estimate Statement or Estimated Direct Expenses theretofore delivered to the extent necessary. Thereafter, Tenant shall pay, with its next installment of Base Rent due that is at least thirty (30) days thereafter, a fraction of the Estimated Direct Expenses for the then-current Expense Year (reduced by any amounts paid pursuant to the last sentence of this Section 4.4.2). Such fraction shall have as its numerator the number of months which have elapsed in such current Expense Year, including the month of such payment, and twelve (12) as its denominator. Until a new Estimate Statement is furnished (which Landlord shall have the right to deliver to Tenant at any time), Tenant shall pay monthly, with the monthly Base Rent installments, an amount equal to one-twelfth (1/12) of the total Estimated Direct Expenses set forth in the previous Estimate Statement delivered by Landlord to Tenant.

4.5 Taxes and Other Charges for Which Tenant Is Directly Responsible. Tenant shall be liable for and shall pay ten (10) days before delinquency, taxes levied against Tenant’s equipment, furniture, fixtures and any other personal property located in or about the Premises. If any such taxes on Tenant’s equipment, furniture, fixtures and any other personal property are levied against Landlord or Landlord’s property or if the assessed value of Landlord’s property is increased by the inclusion therein of a value placed upon such equipment, furniture, fixtures or any other personal property and if Landlord pays the taxes based upon such increased assessment, which Landlord shall have the right to do regardless of the validity thereof but only under proper protest if requested by Tenant, Tenant shall upon demand repay to Landlord the taxes so levied against Landlord or the proportion of such taxes resulting from such increase in the assessment, as the case may be.

4.6 Landlord’s Books and Records. Within one hundred twenty (120) days after receipt by Tenant of a Statement, if Tenant disputes the amount of Additional Rent set forth in the Statement, a member of Tenant’s finance department, or an independent certified public accountant (which accountant is a member of a nationally recognized accounting firm and is not working on a contingency fee basis) (“Tenant’s Accountant”), designated and paid for by Tenant, may, after reasonable notice to Landlord and at reasonable times, inspect Landlord’s records with respect to the Statement at Landlord’s offices, provided that there is no existing Event of Default and Tenant has paid all amounts required to be paid under the applicable Estimate Statement and Statement, as the case may be. In connection with such inspection, Tenant and Tenant’s agents must agree in advance to follow Landlord’s reasonable rules and

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procedures regarding inspections of Landlord’s records, and shall execute a commercially reasonable confidentiality agreement regarding such inspection. Tenant’s failure to dispute the amount of Additional Rent set forth in any Statement within one hundred twenty (120) days of Tenant’s receipt of such Statement shall be deemed to be Tenant’s approval of such Statement and Tenant, thereafter, waives the right or ability to dispute the amounts set forth in such Statement. If after such inspection, Tenant still disputes such Additional Rent, a determination as to the proper amount shall be made, at Tenant’s expense, by an independent certified public accountant (the “Accountant”) selected by Landlord and subject to Tenant’s reasonable approval; provided that if such Accountant determines that Direct Expenses were overstated by more than five percent (5%), then the cost of the Accountant and the cost of such determination shall be paid for by Landlord, and Landlord shall reimburse Tenant’s the cost of the Tenant’s Accountant (provided that such cost shall be a reasonable market cost for such services). Tenant hereby acknowledges that Tenant’s sole right to inspect Landlord’s books and records and to contest the amount of Direct Expenses payable by Tenant shall be as set forth in this Section 4.6, and Tenant hereby waives any and all other rights pursuant to applicable law to inspect such books and records and/or to contest the amount of Direct Expenses payable by Tenant.

5. USE OF PREMISES.

5.1 Permitted Use. Tenant shall use the Premises solely for the Permitted Use set forth in Section 7 of the Summary and Tenant shall not use or permit the Premises or the Project to be used for any other purpose or purposes whatsoever without the prior written consent of Landlord, which may be withheld in Landlord’s sole discretion.

5.2 Prohibited Uses. Tenant further covenants and agrees that Tenant shall not use or permit any person or persons to use, the Premises or any part thereof for any use or purpose in violation of the laws of the United States of America, the State of California, or the ordinances, regulations or requirements of the local municipal or county governing body or other lawful authorities having jurisdiction over the Project) including, without limitation, any such laws, ordinances, regulations or requirements relating to hazardous materials or substances, as those terms are defined by applicable laws now or hereafter in effect. Landlord shall have the right to impose reasonable, nondiscriminatory and customary rules and regulations regarding the use of the Project that do not unreasonably interfere with Tenant’s use of the Premises, as reasonably deemed necessary by Landlord with respect to the orderly operation of the Project, and Tenant shall comply with such reasonable rules and regulations. Tenant shall not do or permit anything to be done in or about the Premises which will in any way obstruct or interfere with the rights of other tenants or occupants of the Building, or injure or annoy them or use or allow the Premises to be used for any improper, unlawful or objectionable purpose, nor shall Tenant cause, maintain or permit any nuisance in, on or about the Premises. Tenant shall comply with, and Tenant’s rights and obligations under the Lease and Tenant’s use of the Premises shall be subject and subordinate to, all recorded easements, covenants, conditions, and restrictions now or hereafter affecting the Project, so long as the same do not unreasonably interfere with Tenant’s use of the Premises or parking rights or materially increase Tenant’s obligations or decrease Tenant’s rights under this Lease.

5.3 Hazardous Materials.

5.3.1 Tenant’s Obligations.

5.3.1.1 Prohibitions. As a material inducement to Landlord to enter into this Lease with Tenant, Tenant has fully and accurately completed Landlord’s Pre-Leasing Environmental Exposure Questionnaire (the “Environmental Questionnaire”), which is attached as Exhibit E. Tenant agrees that except for those chemicals or materials, and their respective quantities, specifically listed on the Environmental Questionnaire (as the same may be updated from time to time as provided below),

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neither Tenant nor Tenant’s employees, contractors and subcontractors of any tier, entities with a contractual relationship with Tenant (other than Landlord), or any entity acting as an agent or sub-agent of Tenant (collectively, “Tenant’s Agents”) will produce, use, store or generate any “Hazardous Materials,” as that term is defined below, on, under or about the Premises, nor cause any Hazardous Material to be brought upon, placed, stored, manufactured, generated, blended, handled, recycled, used or “Released,” as that term is defined below, on, in, under or about the Premises. If any information provided to Landlord by Tenant on the Environmental Questionnaire, or otherwise relating to information concerning Hazardous Materials is intentionally false, incomplete, or misleading in any material respect, the same shall be deemed a default by Tenant under this Lease. Upon Landlord’s request, or in the event of any material change in Tenant’s use of Hazardous Materials in the Premises, Tenant shall deliver to Landlord an updated Environmental Questionnaire at least once a year. Tenant shall notify Landlord prior to using any Hazardous Materials in the Premises not described on the initial Environmental Questionnaire, and, to the extent such use would, in Landlord’s reasonable judgment, cause a material increase in the risk of liability compared to the uses previously allowed in the Premises, such additional use shall be subject to Landlord’s prior consent, which may be withheld in Landlord’s reasonable discretion. Tenant shall not install or permit Tenant’s Agents to install any underground storage tank on the Premises. For purposes of this Lease, “Hazardous Materials” means all flammable explosives, petroleum and petroleum products, waste oil, radon, radioactive materials, toxic pollutants, asbestos, polychlorinated biphenyls (“PCBs”), medical waste, chemicals known to cause cancer or reproductive toxicity, pollutants, contaminants, hazardous wastes, toxic substances or related materials, including without limitation any chemical, element, compound, mixture, solution, substance, object, waste or any combination thereof, which is or may be hazardous to human health, safety or to the environment due to its radioactivity, ignitability, corrosiveness, reactivity, explosiveness, toxicity, carcinogenicity, infectiousness or other harmful or potentially harmful properties or effects, or defined as, regulated as or included in, the definition of “hazardous substances,” “hazardous wastes,” “hazardous materials,” or “toxic substances” under any Environmental Laws. For purposes of this Lease, “Release” or “Released” or “Releases” shall mean any release, deposit, discharge, emission, leaking, spilling, seeping, migrating, injecting, pumping, pouring, emptying, escaping, dumping, disposing, or other movement of Hazardous Materials into the environment. Landlord acknowledges that Tenant will be installing and using fume hoods in the Premises and that emissions of Hazardous Materials into the air in compliance with all Environmental Laws shall not be considered Releases.

5.3.1.2 Notices to Landlord. Tenant shall notify Landlord in writing as soon as possible but in no event later than five (5) days after (i) the occurrence of any actual, alleged or threatened Release of any Hazardous Material in, on, under, from, about or in the vicinity of the Premises (whether past or present), regardless of the source or quantity of any such Release, or (ii) Tenant becomes aware of any regulatory actions, inquiries, inspections, investigations, directives, or any cleanup, compliance, enforcement or abatement proceedings (including any threatened or contemplated investigations or proceedings) relating to or potentially affecting the Premises, or (iii) Tenant becomes aware of any claims by any person or entity relating to any Hazardous Materials in, on, under, from, about or in the vicinity of the Premises, whether relating to damage, contribution, cost recovery, compensation, loss or injury. Collectively, the matters set forth in clauses (i), (ii) and (iii) above are hereinafter referred to as “Hazardous Materials Claims”. Tenant shall promptly forward to Landlord copies of all orders, notices, permits, applications and other communications and reports in connection with any Hazardous Materials Claims. Additionally, Tenant shall promptly advise Landlord in writing of Tenant’s discovery of any occurrence or condition on, in, under or about the Premises that could subject Tenant or Landlord to any liability, or restrictions on ownership, occupancy, transferability or use of the Premises under any “Environmental Laws,” as that term is defined below. Tenant shall not enter into any legal proceeding or other action, settlement, consent decree or other compromise with respect to any Hazardous Materials Claims without first notifying Landlord of Tenant’s intention to do so and affording Landlord the opportunity to join and participate, as a party if Landlord so elects, in such proceedings and in no event

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shall Tenant enter into any agreements which are binding on Landlord or the Premises without Landlord’s prior written consent. Landlord shall have the right to appear at and participate in, any and all legal or other administrative proceedings concerning any Hazardous Materials Claim. For purposes of this Lease, “Environmental Laws” means all applicable present and future laws relating to the protection of human health, safety, wildlife or the environment, including, without limitation, (i) all requirements pertaining to reporting, licensing, permitting, investigation and/or remediation of emissions, discharges, Releases, or threatened Releases of Hazardous Materials, whether solid, liquid, or gaseous in nature, into the air, surface water, groundwater, or land, or relating to the manufacture, processing, distribution, use, treatment, storage, disposal, transport, or handling of Hazardous Materials; and (ii) all requirements pertaining to the health and safety of employees or the public. Environmental Laws include, but are not limited to, the Comprehensive Environmental Response, Compensation and Liability Act of 1980, 42 USC § 9601, et seq., the Hazardous Materials Transportation Authorization Act of 1994, 49 USC § 5101, et seq., the Solid Waste Disposal Act, as amended by the Resource Conservation and Recovery Act of 1976, and Hazardous and Solid Waste Amendments of 1984, 42 USC § 6901, et seq., the Federal Water Pollution Control Act, as amended by the Clean Water Act of 1977, 33 USC § 1251, et seq., the Clean Air Act of 1966, 42 USC § 7401, et seq., the Toxic Substances Control Act of 1976, 15 USC § 2601, et seq., the Safe Drinking Water Act of 1974, 42 USC §§ 300f through 300j, the Occupational Safety and Health Act of 1970, as amended, 29 USC § 651 et seq., the Oil Pollution Act of 1990, 33 USC § 2701 et seq., the Emergency Planning and Community Right-To-Know Act of 1986, 42 USC § 11001 et seq., the National Environmental Policy Act of 1969, 42 USC § 4321 et seq., the Federal Insecticide, Fungicide and Rodenticide Act of 1947, 7 USC § 136 et seq., California Carpenter-Presley-Tanner Hazardous Substance Account Act, California Health & Safety Code §§ 25300 et seq., Hazardous Materials Release Response Plans and Inventory Act, California Health & Safety Code, §§ 25500 et seq., Underground Storage of Hazardous Substances provisions, California Health & Safety Code, §§ 25280 et seq., California Hazardous Waste Control Law, California Health & Safety Code, §§ 25100 et seq., and any other state or local law counterparts, as amended, as such applicable laws, are in effect as of the Lease Commencement Date, or thereafter adopted, published, or promulgated.

5.3.1.3 Releases of Hazardous Materials. If any Release of any Hazardous Material in, on, under, from or about the Premises shall occur at any time during the Lease by Tenant or Tenant’s Agents, in addition to notifying Landlord as specified above, Tenant, at its own sole cost and expense, shall (i) immediately comply with any and all reporting requirements imposed pursuant to any and all Environmental Laws, (ii) provide a written certification to Landlord indicating that Tenant has complied with all applicable reporting requirements, (iii) take any and all necessary investigation, corrective and remedial action in accordance with any and all applicable Environmental Laws, utilizing an environmental consultant approved by Landlord, all in accordance with the provisions and requirements of this Section 5.3, including, without limitation, Section 5.3.4, and (iv) take any such additional investigative, remedial and corrective actions as Landlord shall in its reasonable discretion deem necessary such that the Premises are remediated to the condition existing prior to such Release.

5.3.1.4 Indemnification.

5.3.1.4.1 In General. Without limiting in any way Tenant’s obligations under any other provision of this Lease, Tenant shall be solely responsible for and shall protect, defend, indemnify and hold the Landlord Parties harmless from and against any and all claims, judgments, losses, damages, costs, expenses, penalties, enforcement actions, taxes, fines, remedial actions, liabilities (including, without limitation, actual attorneys’ fees, litigation, arbitration and administrative proceeding costs, expert and consultant fees and laboratory costs) including, without limitation, consequential damages and sums paid in settlement of claims, which arise during or after the Lease Term, whether foreseeable or unforeseeable, that arise during or after the Lease Term in whole or in part, foreseeable or unforeseeable, directly or indirectly arising out of or attributable to the Release of Hazardous Materials in, on, under or about the Premises by Tenant or Tenant’s Agents.

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5.3.1.4.2 Limitations. Notwithstanding anything in Section 5.3.1.4, above, to the contrary, Tenant’s indemnity of Landlord as set forth in Section 5.3.1.4, above, shall not be applicable to claims based upon Hazardous Materials not Released by Tenant or Tenant’s Agents.

5.3.1.4.3 Landlord Indemnity. Under no circumstance shall Tenant be liable for, and Landlord shall indemnify, defend, protect and hold harmless Tenant and Tenant’s Agents from and against, all losses, costs, claims, liabilities and damages (including attorneys’ and consultants’ fees) arising out of any Hazardous Materials that exist in, on or about the Project as of the date hereof, or Hazardous Material Released by Landlord or any Landlord Parties. Landlord will provide Tenant with any Hazardous Material reports relating to the Building that Landlord has in its immediate possession. The provision of such reports shall be for informational purposes only, and Landlord does not make any representation or warranty as to the correctness or completeness of any such reports.

5.3.1.5 Compliance with Environmental Laws. Without limiting the generality of Tenant’s obligation to comply with applicable laws as otherwise provided in this Lease, Tenant shall, at its sole cost and expense, comply with all Environmental Laws related to the use of Hazardous Materials by Tenant and Tenant’s Agents. Tenant shall obtain and maintain any and all necessary permits, licenses, certifications and approvals appropriate or required for the use, handling, storage, and disposal of any Hazardous Materials used, stored, generated, transported, handled, blended, or recycled by Tenant on the Premises. Landlord shall have a continuing right, without obligation, to require Tenant to obtain, and to review and inspect any and all such permits, licenses, certifications and approvals, together with copies of any and all Hazardous Materials management plans and programs, any and all Hazardous Materials risk management and pollution prevention programs, and any and all Hazardous Materials emergency response and employee training programs respecting Tenant’s use of Hazardous Materials. Upon request of Landlord, Tenant shall deliver to Landlord a narrative description explaining the nature and scope of Tenant’s activities involving Hazardous Materials and showing to Landlord’s satisfaction compliance with all Environmental Laws and the terms of this Lease.

5.3.2 Assurance of Performance.

5.3.2.1 Environmental Assessments In General. Landlord may, but shall not be required to, engage from time to time such contractors as Landlord determines to be appropriate (and which are reasonably acceptable to Tenant) to perform environmental assessments of a scope reasonably determined by Landlord (an “Environmental Assessment”) to ensure Tenant’s compliance with the requirements of this Lease with respect to Hazardous Materials.

5.3.2.2 Costs of Environmental Assessments. All costs and expenses incurred by Landlord in connection with any such Environmental Assessment initially shall be paid by Landlord; provided that if any such Environmental Assessment shows that Tenant has failed to comply with the provisions of this Section 5.3, then all of the costs and expenses of such Environmental Assessment shall be reimbursed by Tenant as Additional Rent within thirty (30) days after receipt of written demand therefor.

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5.3.3 Tenant’s Obligations upon Surrender. At the expiration or earlier termination of the Lease Term, Tenant, at Tenant’s sole cost and expense, shall: (i) cause an Environmental Assessment of the Premises to be conducted in accordance with Section 15.3; (ii) cause all Hazardous Materials brought onto the Premises by Tenant or Tenant’s Agents to be removed from the Premises and disposed of in accordance with all Environmental Laws and as necessary to allow the Premises to be used for the purposes allowed as of the date of this Lease; and (iii) cause to be removed all containers installed or used by Tenant or Tenant’s Agents to store any Hazardous Materials on the Premises, and cause to be repaired any damage to the Premises caused by such removal.

5.3.4 Clean-up.

5.3.4.1 Environmental Reports; Clean-Up. If any written report, including any report containing results of any Environmental Assessment (an “Environmental Report”) shall indicate (i) the presence of any Hazardous Materials as to which Tenant has a removal or remediation obligation under this Section 5.3, and (ii) that as a result of same, the investigation, characterization, monitoring, assessment, repair, closure, remediation, removal, or other clean-up (the “Clean-up”) of any Hazardous Materials is required, Tenant shall immediately prepare and submit to Landlord within thirty (30) days after receipt of the Environmental Report a comprehensive plan, subject to Landlord’s written approval, specifying the actions to be taken by Tenant to perform the Clean-up so that the Premises are restored to the conditions required by this Lease. Upon Landlord’s approval of the Clean-up plan, Tenant shall, at Tenant’s sole cost and expense, without limitation on any rights and remedies of Landlord under this Lease, immediately implement such plan with a consultant reasonably acceptable to Landlord and proceed to Clean-Up Hazardous Materials in accordance with all applicable laws. If, within thirty (30) days after receiving a copy of such Environmental Report, Tenant fails either (a) to complete such Clean-up, or (b) with respect to any Clean-up that cannot be completed within such thirty-day period, fails to proceed with diligence to prepare the Clean-up plan and complete the Clean-up as promptly as practicable, then Landlord shall have the right, but not the obligation, and without waiving any other rights under this Lease, to carry out any Clean-up recommended by the Environmental Report or required by any governmental authority having jurisdiction over the Premises, and recover all of the costs and expenses thereof from Tenant as Additional Rent, payable within ten (10) days after receipt of written demand therefor.

5.3.4.2 No Rent Abatement. Tenant shall continue to pay all Rent due or accruing under this Lease during any Clean-up, and shall not be entitled to any reduction, offset or deferral of any Base Rent or Additional Rent due or accruing under this Lease during any such Clean-up.

5.3.4.3 Surrender of Premises. Tenant shall complete any Clean-up prior to surrender of the Premises upon the expiration or earlier termination of this Lease. Tenant shall obtain and deliver to Landlord a letter or other written determination from the overseeing governmental authority confirming that the Clean-up has been completed in accordance with all requirements of such governmental authority and that no further response action of any kind is required for the unrestricted use of the Premises (“Closure Letter”). Upon the expiration or earlier termination of this Lease, Tenant shall also be obligated to close all permits obtained in connection with Hazardous Materials used by Tenant or Tenant’s Agents in accordance with applicable laws.

5.3.4.4 Failure to Timely Clean-Up. Should any Clean-up for which Tenant is responsible not be completed, or should Tenant not receive the Closure Letter and any governmental approvals required under Environmental Laws in conjunction with such Clean-up prior to the expiration or earlier termination of this Lease, then, commencing on the later of the termination of this Lease and three (3) business days after Landlord’s delivery of notice of such failure and that it elects to treat such failure as a holdover, Tenant shall be liable to Landlord as a holdover tenant (as more particularly provided in Article 16) until Tenant has fully complied with its obligations under this Section 5.3.

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5.3.5 Confidentiality. Unless compelled to do so by applicable law, Tenant agrees that Tenant shall not disclose, discuss, disseminate or copy any information, data, findings, communications, conclusions and reports regarding the environmental condition of the Premises to any Person (other than Tenant’s consultants, attorneys, property managers, employees, shareholders and potential and actual investors, lenders, business and merger partners, subtenants and assignees that have a need to know such information), including any governmental authority, without the prior written consent of Landlord. In the event Tenant reasonably believes that disclosure is compelled by applicable law, it shall provide Landlord ten (10) days’ advance notice of disclosure of confidential information so that Landlord may attempt to obtain a protective order. Tenant may additionally release such information to bona fide prospective purchasers or lenders, subject to any such parties’ written agreement to be bound by the terms of this Section 5.3.

5.3.6 Copies of Environmental Reports. Within thirty (30) days of receipt thereof, Tenant shall provide Landlord with a copy of any and all environmental assessments, audits, studies and reports regarding Tenant’s activities with respect to the Premises, or ground water beneath the Land, or the environmental condition or Clean-up thereof. Tenant shall be obligated to provide Landlord with a copy of such materials without regard to whether such materials are generated by Tenant or prepared for Tenant, or how Tenant comes into possession of such materials.

5.3.7 Signs, Response Plans, Etc. Tenant shall be responsible for posting on the Premises any signs required under applicable Environmental Laws with respect to the use of Hazardous Materials by Tenant or Tenant’s Agents. Tenant shall also complete and file any business response plans or inventories required by any applicable laws. Tenant shall concurrently file a copy of any such business response plan or inventory with Landlord.

5.3.8 Survival. Each covenant, agreement, representation, warranty and indemnification made by Tenant set forth in this Section 5.3 shall survive the expiration or earlier termination of this Lease and shall remain effective until all of Tenant’s obligations under this Section 5.3 have been completely performed and satisfied.

6. SERVICES AND UTILITIES.

6.1 In General. Landlord will be responsible, at Tenant’s sole cost and expense (subject to the terms of Section 4.2.4, above), for the furnishing of heating, ventilation and air-conditioning, electricity, water, and interior Building security services to the Premises. Landlord shall not provide janitorial or telephone services for the Premises. Tenant shall be solely responsible for performing all janitorial services and other cleaning of the Premises, all in compliance with applicable laws. The janitorial and cleaning of the Premises shall be adequate to maintain the Premises in a manner consistent with First Class Life Sciences Projects.

Tenant shall cooperate fully with Landlord at all times and abide by all reasonable regulations and requirements that Landlord may reasonably prescribe for the proper functioning and protection of the HVAC, electrical, mechanical and plumbing systems. Provided that Landlord agrees to provide and maintain and keep in continuous service utility connections to the Project, including electricity, water and sewage connections, Landlord shall have no obligation to provide any services or utilities to the Building, including, but not limited to heating, ventilation and air-conditioning, electricity, water, telephone, janitorial and interior Building security services, except as set forth in this Section 6.1, above.

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6.2 Tenant Payment of Utilities Costs. After the Lease Commencement Date, to the extent that any utilities (including without limitation, electricity, gas, sewer and water) to the Building are separately metered or sub-metered to the Premises, such utilities shall either be contracted for and paid directly by Tenant to the applicable utility provider, or reimbursed by Tenant to Landlord within thirty (30) days after billing. After the Lease Commencement Date, to the extent that any utilities (including without limitation, electricity, gas, sewer and water) to the Building are not separately metered to the Premises, then Tenant shall pay to Landlord, within thirty (30) days after billing, an equitable portion of the Building utility costs, based on Tenant’s proportionate use thereof. In connection with the foregoing, Landlord shall install separate meters on the Building Systems as a part of Landlord’s construction of the Base Building, and Tenant shall install separate meters on the systems installed in the Premises as part of the Tenant Improvements pursuant to the Work Letter.

6.3 Interruption of Use. Tenant agrees that Landlord shall not be liable for damages, by abatement of Rent or otherwise, for failure to furnish or delay in furnishing any service or utility (including, without limitation, telephone and telecommunication services, UPS services, or other laboratory services or utilities), or for any diminution in the quality or quantity thereof, when such failure or delay or diminution is occasioned, in whole or in part, by breakage, repairs, replacements, or improvements, by any strike, lockout or other labor trouble, by inability to secure electricity, gas, water, or other fuel at the Building or Project after reasonable effort to do so, by any riot or other dangerous condition, emergency, accident or casualty whatsoever, by act or default of Tenant or other parties, or by any other cause; and such failures or delays or diminution shall never be deemed to constitute an eviction or disturbance of Tenant’s use and possession of the Premises or relieve Tenant from paying Rent or performing any of its obligations under this Lease. Notwithstanding the foregoing, Landlord may be liable for damages to the extent caused by the negligence or willful misconduct of Landlord or the Landlord Parties, provided that Landlord shall not be liable under any circumstances for injury to, or interference with, Tenant’s business, including, without limitation, loss of profits, however occurring, through or in connection with or incidental to a failure to furnish any of the services or utilities as set forth in this Article 6.

6.4 Energy Performance Disclosure Information. Tenant hereby acknowledges that Landlord may be required to disclose certain information concerning the energy performance of the Building pursuant to California Public Resources Code Section 25402.10 and the regulations adopted pursuant thereto (collectively the “Energy Disclosure Requirements”). Tenant hereby acknowledges prior receipt of the Data Verification Checklist, as defined in the Energy Disclosure Requirements (the “Energy Disclosure Information”), and agrees that Landlord has timely complied in full with Landlord’s obligations under the Energy Disclosure Requirements. Tenant acknowledges and agrees that (i) Landlord makes no representation or warranty regarding the energy performance of the Building or the accuracy or completeness of the Energy Disclosure Information, (ii) the Energy Disclosure Information is for the current occupancy and use of the Building and that the energy performance of the Building may vary depending on future occupancy and/or use of the Building, and (iii) Landlord shall have no liability to Tenant for any errors or omissions in the Energy Disclosure Information. If and to the extent not prohibited by applicable laws, Tenant hereby waives any right Tenant may have to receive the Energy Disclosure Information, including, without limitation, any right Tenant may have to terminate this Lease as a result of Landlord’s failure to disclose such information. Further, Tenant hereby releases Landlord 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 Landlord’s failure to disclose the Energy Disclosure Information to Tenant prior to the execution of this Lease. Tenant’s acknowledgment of the AS-IS condition of the Premises pursuant to the terms of this Lease shall be deemed to include the energy performance of the Building. Tenant further acknowledges that pursuant to the Energy Disclosure Requirements, Landlord may be required in the future to disclose information concerning Tenant’s energy usage to certain third parties, including, without limitation, prospective purchasers, lenders and tenants of the Building (the “Tenant Energy Use Disclosure”). Tenant hereby (A) consents to all such Tenant Energy Use Disclosures, and (B) acknowledges that Landlord shall not be required to notify Tenant of any Tenant Energy Use Disclosure.

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Further, Tenant hereby releases Landlord from any and all losses, costs, damages, expenses and liabilities relating to, arising out of and/or resulting from any Tenant Energy Use Disclosure. The terms of this Section 6.3 shall survive the expiration or earlier termination of this Lease.

6.5 Existing Generator. Commencing on the Lease Commencement Date, Tenant shall have the right to connect to the Building back-up generator, which Landlord shall install as part of Landlord’s Work (the “Generator”), for Tenant’s Share of the Generator’s capacity to provide back-up generator services to the Premises. During the Lease Term, Landlord shall maintain the Generator in good condition and repair, and Tenant shall be responsible for a share of the costs of such maintenance and repair based on the proportion of the Generator capacity allocated to the Premises. Notwithstanding the foregoing, Landlord shall not be liable for any damages whatsoever resulting from any failure in operation of the Generator, or the failure of the Generator to provide suitable or adequate back-up power to the Premises, including but not limited to, loss of profits, loss of rents or other revenues, loss of business opportunity, loss of goodwill or loss of use, in each case, however occurring, or loss to inventory, scientific research, scientific experiments, laboratory animals, products, specimens, samples, and/or scientific, business, accounting and other records of every kind and description kept at the Premises and any and all income derived or derivable therefrom.

6.6 Chemical Storage Room. Tenant shall have the right to utilize storage space in the chemical storage room to be constructed by Landlord in the Building pursuant to Schedule 1 to Exhibit B (the “Chemical Storage Room”), for up to Tenant’s Share of the Chemical Storage Room’s storage capacity, provided that Tenant shall be responsible for providing any equipment or modifications (e.g., (self-contained bunkers, dedicated exhaust, additional fire rating, etc.) to support Tenant’s specific usage. During the Lease Term, Landlord shall maintain the Chemical Storage Room in good condition and repair, and Tenant shall be responsible for a share of the costs of such maintenance and repair based on the proportion of the capacity of the Chemical Storage Room allocated to Tenant’s use (subject to the provisions of Section 4.2.4 above). Notwithstanding the foregoing, Landlord shall not be liable for any damages whatsoever resulting from any failure in operation of the Chemical Storage Room, or the failure of the Chemical Storage Room to provide suitable or adequate storage of Tenant’s chemicals, including but not limited to, loss of profits, loss of rents or other revenues, loss of business opportunity, loss of goodwill or loss of use, in each case, however occurring, or loss to inventory, scientific research, scientific experiments, laboratory animals, products, specimens, samples, and/or scientific, business, accounting and other records of every kind and description kept at the Chemical Storage Room or the Premises and any and all income derived or derivable therefrom.

7. REPAIRS.

7.1 Tenant Repair Obligations. Tenant shall, throughout the Term, at its sole cost and expense, maintain, repair or replace as required, the Premises in a good standard of maintenance, repair and replacement as required, and in good and sanitary condition, all in accordance with the standards of First Class Life Sciences Projects, except for the Landlord Repair Obligations, whether or not such maintenance, repair, replacement or improvement is required in order to comply with applicable Laws (“Tenant’s Repair Obligations”), including without limitation, all electrical facilities and equipment, including lighting fixtures, lamps, fans and any exhaust equipment and systems, electrical motors and all other appliances and equipment of every kind and nature located in the Premises; all communications systems serving the Premises; all of Tenant’s security systems in or about or serving the Premises; Tenant’s signage; interior demising walls and partitions (including painting and wall coverings), equipment, floors. Tenant shall additionally be responsible, at Tenant’s sole cost and expense, to furnish all expendables, including light bulbs, paper goods and soaps, used in the Premises.

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7.2 Landlord Repair Obligations. Landlord shall be responsible, as a part of Operating Expenses, for repairs to and routine maintenance of the Building including without limitation: (1) exterior windows, window frames, window casements (including the repairing, resealing, cleaning and replacing of exterior windows); (2) exterior doors, door frames and door closers; (3) the Building (as opposed to the Premises) and Project plumbing, sewer, drainage, electrical, fire protection, life safety and security systems and equipment, existing heating, ventilation and air-conditioning systems, and all other mechanical and HVAC systems and equipment (collectively, the “Building Systems”), (4) the exterior glass, exterior walls, foundation and roof of the Building, the structural portions of the floors of the Building, including, without limitation, any painting, sealing, patching and waterproofing of exterior walls, and (5) repairs to the elevator in the Building and underground utilities, except to the extent that any such repairs are required due to the negligence or willful misconduct of Tenant (the “Landlord Repair Obligations”); provided, however, that if such repairs are due to the negligence or willful misconduct of Tenant, Landlord shall nevertheless make such repairs at Tenant’s expense, or, if covered by Landlord’s insurance, Tenant shall only be obligated to pay any deductible in connection therewith. Costs expended by Landlord in connection with the Landlord Repair Obligations shall be included in Operating Expenses to the extent allowed pursuant to the terms of Article 4, above. Landlord shall cooperate with Tenant to enforce any warranties that Landlord holds that could reduce Tenant’s maintenance obligations under this Lease.

7.3 Tenant’s Right to Make Repairs. Notwithstanding any provision to the contrary contained in this Lease, if Tenant provides written notice to Landlord of an event or circumstance which requires the action of Landlord under this Lease with respect to repair and/or maintenance required in the Premises, including repairs to the portions of the Building located within the Premises that are Landlord’s responsibility under Section 7.4 (the “Base Building”), which event or circumstance with respect to the Base Building materially and adversely affects the conduct of Tenant’s business from the Premises, and Landlord fails to commence corrective action within a reasonable period of time, given the circumstances, after the receipt of such notice, but in any event not later than thirty (30) days after receipt of said notice (unless Landlord’s obligation cannot reasonably be performed within thirty (30) days, in which event Landlord shall be allowed additional time as is reasonably necessary to perform the obligation so long as Landlord begins performance within the initial thirty (30) days and diligently pursues performance to completion), or, in the event of an Emergency (as defined below), not later than five (5) business days after receipt of such notice, then Tenant shall have the right to undertake such actions as may be reasonably necessary to make such repairs if Landlord thereafter fails to commence corrective action within five (5) business days following Landlord’s receipt of a second written notice from Tenant specifying that Tenant will undertake such actions if Landlord fails to timely do so (provided that such notice shall include the following language in bold, capitalized text: “IF LANDLORD FAILS TO COMMENCE THE REPAIRS DESCRIBED IN THIS LETTER WITHIN FIVE (5) BUSINESS DAYS FROM LANDLORD’S RECEIPT OF THIS LETTER, TENANT WILL PERFORM SUCH REPAIRS AT LANDLORD’S EXPENSE”; provided, however, that in no event shall Tenant undertake any actions that could materially or adversely affect the Base Building. Notwithstanding the foregoing, in the event of an Emergency, no second written notice shall be required as long as Tenant advises Landlord in the first written notice of Tenant’s intent to perform such Emergency repairs if Landlord does not commence the same within such five (5) business day period, utilizing the language required in second notices. If such action was required under the terms of this Lease to be taken by Landlord and was not commenced by Landlord within such five (5) business day period and thereafter diligently pursued to completion, then Tenant shall be entitled to prompt reimbursement by Landlord of the reasonable out-of-pocket third-party costs and expenses actually incurred by Tenant in taking such action. If Tenant undertakes such corrective actions pursuant to this Section 7.3, then (a) the insurance and indemnity provisions set forth in this Lease shall apply to Tenant’s performance of such corrective actions, (b) Tenant shall proceed in accordance with all applicable laws, (c) Tenant shall retain to perform such corrective actions only such reputable contractors and suppliers as are duly licensed and qualified,

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(d) Tenant shall effect such repairs in a good and workmanlike and commercially reasonable manner, (e) Tenant shall use new or like new materials, and (f) Tenant shall take reasonable efforts to minimize any material interference or impact on the other tenants and occupants of the Building. Promptly following completion of any work taken by Tenant pursuant to the terms of this Section 7.5, Tenant shall deliver a detailed invoice of the work completed, the materials used and the costs relating thereto, and Landlord shall reimburse Tenant the amounts expended by Tenant in connection with such work, provided that Landlord shall have the right to object if Landlord claims that such action did not have to be taken by Landlord pursuant to the terms of this Lease or that the charges are excessive (in which case Landlord shall pay the amount it contends would not have been excessive). For purposes of this Section 7.5, an “Emergency” shall mean an event threatening immediate and material danger to people located in the Building or immediate, material damage to the Building, Base Building, or creating a realistic possibility of an immediate and material interference with, or immediate and material interruption of a material aspect of Tenant’s business operations.

8. ADDITIONS AND ALTERATIONS.

8.1 Landlord’s Consent to Alterations. Tenant may not make any improvements, alterations, additions or changes to the Premises or any mechanical, plumbing or HVAC facilities or systems pertaining to the Premises (collectively, the “Alterations”) without first procuring the prior written consent of Landlord to such Alterations, which consent shall be requested by Tenant not less than ten (10) business days prior to the commencement thereof, and which consent shall not be unreasonably withheld by Landlord, provided it shall be deemed reasonable for Landlord to withhold its consent to any Alteration which adversely affects the structural portions or the systems or equipment of the Building or is visible from the exterior of the Building. Notwithstanding the foregoing, Tenant shall be permitted to make Alterations following ten (10) business days’ notice to Landlord (as to Alterations costing more than $10,000 only), but without Landlord’s prior consent, to the extent that such Alterations (i) do not affect the building systems or equipment (other than minor changes such as adding or relocating electrical outlets and thermostats), (ii) are not visible from the exterior of the Building, and (iii) cost less than $50,000.00 for a particular job of work. The construction of the Tenant Improvements to the Premises shall be governed by the terms of the Tenant Work Letter and not the terms of this Article 8.

8.2 Manner of Construction. Landlord may impose, as a condition of its consent to any and all Alterations or repairs of the Premises or about the Premises, such requirements as Landlord in its reasonable discretion may deem desirable, including, but not limited to, the requirement that upon Landlord’s request, Tenant shall, at Tenant’s expense, remove such Alterations upon the expiration or any early termination of the Lease Term. Tenant shall construct such Alterations and perform such repairs in a good and workmanlike manner, in conformance with any and all applicable federal, state, county or municipal laws, rules and regulations and pursuant to a valid building permit, issued by the city in which the Building is located (or other applicable governmental authority). Tenant shall not use (and upon notice from Landlord shall cease using) contractors, services, workmen, labor, materials or equipment that, in Landlord’s reasonable judgment, would disturb labor harmony with the workforce or trades engaged in performing other work, labor or services in or about the Building or the Common Areas. Upon completion of any Alterations, Tenant shall deliver to Landlord final lien waivers from all contractors, subcontractors and materialmen who performed such work. In addition to Tenant’s obligations under Article 9 of this Lease, upon completion of any Alterations, Tenant agrees to cause a Notice of Completion to be recorded in the office of the Recorder of the County of San Mateo in accordance with Section 3093 of the Civil Code of the State of California or any successor statute, and Tenant shall deliver to the Project construction manager a reproducible copy of the “as built” drawings of the Alterations as well as all permits, approvals and other documents issued by any governmental agency in connection with the Alterations.

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8.3 Payment for Improvements. In connection with any Alterations that affect the Building systems (other than minor changes such as adding or relocating electrical outlets and thermostats), or which have a cost in excess of $100,000, Tenant shall reimburse Landlord for Landlord’s reasonable, actual, out-of-pocket costs and expenses actually incurred in connection with Landlord’s review of such work.

8.4 Construction Insurance. In addition to the requirements of Article 10 of this Lease, in the event that Tenant makes any Alterations, prior to the commencement of such Alterations, Tenant shall provide Landlord with evidence that Tenant or Tenant’s contractor carries “Builder’s All Risk” insurance (to the extent that the cost of such work shall exceed $50,000) in an amount approved by Landlord covering the construction of such Alterations, and such other insurance as Landlord may reasonably require, it being understood and agreed that all of such Alterations shall be insured by Landlord pursuant to Article 10 of this Lease immediately upon completion thereof. In addition, Tenant’s contractors and subcontractors shall be required to carry Commercial General Liability Insurance in an amount approved by Landlord and otherwise in accordance with the requirements of Article 10 of this Lease. In connection with Alterations with a cost in excess of $250,000, Landlord may, in its reasonable discretion, require Tenant to obtain a lien and completion bond or some alternate form of security satisfactory to Landlord in an amount sufficient to ensure the lien-free completion of such Alterations and naming Landlord as a co-obligee.

8.5 Landlord’s Property. All Alterations, improvements, fixtures, equipment and/or appurtenances which may be installed or placed in or about the Premises, from time to time, shall be at the sole cost of Tenant and all Alterations and improvements, shall be and become the property of Landlord and remain in place at the Premises following the expiration or earlier termination of this Lease. Notwithstanding the foregoing, Landlord may, by written notice to Tenant given at the time it consents to an Alteration, require Tenant, at Tenant’s expense, to remove any Alterations within the Premises and to repair any damage to the Premises and Building caused by such removal. If Tenant fails to complete such removal and/or to repair any damage caused by the removal of any Alterations, Landlord may do so and may charge the cost thereof to Tenant. Tenant hereby protects, defends, indemnifies and holds Landlord harmless from any liability, cost, obligation, expense or claim of lien in any manner relating to the installation, placement, removal or financing of any such Alterations, improvements, fixtures and/or equipment in, on or about the Premises, which obligations of Tenant shall survive the expiration or earlier termination of this Lease. Notwithstanding the foregoing, except to the extent the same are paid for by the Tenant Improvement Allowance, the items set forth in Exhibit F attached hereto (the “Tenant’s Property”) shall at all times be and remain Tenant’s property. Exhibit F may be updated from time to time by agreement of the parties. Tenant may remove the Tenant’s Property from the Premises at any time, provided that Tenant repairs all damage caused by such removal. Landlord shall have no lien or other interest in the Tenant’s Property.

9. COVENANT AGAINST LIENS. Tenant shall keep the Project and Premises free from any liens or encumbrances arising out of the work performed, materials furnished or obligations incurred by or on behalf of Tenant, and shall protect, defend, indemnify and hold Landlord harmless from and against any claims, liabilities, judgments or costs (including, without limitation, reasonable attorneys’ fees and costs) arising out of same or in connection therewith. Except as to Alterations as to which no notice is required under the second sentence of Section 8.1, Tenant shall give Landlord notice at least ten (10) business days prior to the commencement of any such work on the Premises (or such additional time as may be necessary under applicable laws) to afford Landlord the opportunity of posting and recording appropriate notices of non-responsibility (to the extent applicable pursuant to then applicable laws). Tenant shall remove any such lien or encumbrance by bond or otherwise within ten (10) business days after notice by Landlord, and if Tenant shall fail to do so, Landlord may pay the amount necessary to remove such lien or encumbrance, without being responsible for investigating the validity thereof.

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10. INSURANCE.

10.1 Indemnification and Waiver. Except as provided in Section 10.5 or to the extent due to the negligence, willful misconduct or violation of this Lease by Landlord or the Landlord Parties, Tenant hereby assumes all risk of damage to property in, upon or about the Premises from any cause whatsoever (including, but not limited to, any personal injuries resulting from a slip and fall in, upon or about the Premises) and agrees that Landlord, its partners, subpartners and their respective officers, agents, servants, employees, and independent contractors (collectively, “Landlord Parties”) shall not be liable for, and are hereby released from any responsibility for, any damage either to person or property or resulting from the loss of use thereof, which damage is sustained by Tenant or by other persons claiming through Tenant. Tenant shall indemnify, defend, protect, and hold harmless the Landlord Parties from any and all loss, cost, damage, expense and liability (including without limitation court costs and reasonable attorneys’ fees) incurred in connection with or arising from any cause in, on or about the Premises (including, but not limited to, a slip and fall), any acts, omissions or negligence of Tenant or of any person claiming by, through or under Tenant, or of the contractors, agents, servants, employees, invitees, guests or licensees of Tenant or any such person, in, on or about the Project or any breach of the terms of this Lease, either prior to, during, or after the expiration of the Lease Term, provided that the terms of the foregoing indemnity and release shall not apply to the negligence or willful misconduct of Landlord or its agents, employees, contractors, licensees or invitees, or Landlord’s violation of this Lease. Should Landlord be named as a defendant in any suit brought against Tenant in connection with or arising out of Tenant’s occupancy of the Premises, Tenant shall pay to Landlord its costs and expenses incurred in such suit, including without limitation, its actual professional fees such as reasonable appraisers’, accountants’ and attorneys’ fees. Notwithstanding anything to the contrary in this Lease, Landlord shall not be released or indemnified from, and shall indemnify, defend, protect and hold harmless Tenant from, all losses, damages, liabilities, claims, attorneys’ fees, costs and expenses arising from the gross negligence or willful misconduct of Landlord or its agents, contractors, licensees or invitees, or a violation of Landlord’s obligations or representations under this Lease. The provisions of this Section 10.1 shall survive the expiration or sooner termination of this Lease with respect to any claims or liability arising in connection with any event occurring prior to such expiration or termination.

10.2 Tenant’s Compliance With Landlord’s Property Insurance. Landlord shall insure the Building, Tenant Improvements and any Alterations during the Lease Term against loss or damage under an “all risk” property insurance policy. Such coverage shall be in such amounts, from such companies, and on such other terms and conditions, as Landlord may from time to time reasonably determine. Additionally, at the option of Landlord, such insurance coverage may include the risks of earthquakes and/or flood damage and additional hazards, a rental loss endorsement and one or more loss payee endorsements in favor of the holders of any mortgages or deeds of trust encumbering the interest of Landlord in the Building or the ground or underlying lessors of the Building, or any portion thereof. The costs of such insurance shall be included in Operating Expenses, subject to the terms of Section 4.2.4. Tenant shall, at Tenant’s expense, comply with all insurance company requirements pertaining to the use of the Premises. If Tenant’s conduct or use of the Premises causes any increase in the premium for such insurance policies then Tenant shall reimburse Landlord for any such increase. Tenant, at Tenant’s expense, shall comply with all rules, orders, regulations or requirements of the American Insurance Association (formerly the National Board of Fire Underwriters) and with any similar body. Notwithstanding anything to the contrary in this Lease, Tenant shall not be required to comply with or cause the Premises to comply with any laws, rules, regulations or insurance requirements requiring the construction of alterations unless such compliance is necessitated solely due to Tenant’s particular use of the Premises.

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10.3 Tenant’s Insurance. Tenant shall maintain the following coverages in the following amounts during the Lease Term (except Tenant shall carry the insurance described in Section 10.3.1 during any period in which it enters the Premises).

10.3.1 Commercial General Liability Insurance on an occurrence form covering the insured against claims of bodily injury and property damage (including loss of use thereof) arising out of Tenant’s operations, and contractual liabilities including a contractual coverage for limits of liability (which limits may be met together with umbrella liability insurance) of not less than:

10.3.2 Property Insurance covering all office furniture, business and trade fixtures, office and lab equipment, free-standing cabinet work, movable partitions, merchandise and all other items of Tenant’s property on the Premises installed by, for, or at the expense of Tenant. Such insurance shall be written on an “all risks” of physical loss or damage basis, for the full replacement cost value (subject to reasonable deductible amounts) new without deduction for depreciation of the covered items and in amounts that meet any co-insurance clauses of the policies of insurance and shall include coverage for damage or other loss caused by fire or other peril including, but not limited to, vandalism and malicious mischief, theft, water damage (excluding flood), including sprinkler leakage, bursting or stoppage of pipes, and explosion, and providing business interruption coverage for a period of ninety (90) days.

10.3.3 Business Income Interruption for ninety (90) days plus Extra Expense insurance in such amounts as will reimburse Tenant for actual direct or indirect loss of earnings attributable to the risks outlined in Section 10.3.2 above.

10.3.4 Worker’s Compensation and Employer’s Liability or other similar insurance pursuant to all applicable state and local statutes and regulations. The policy shall include a waiver of subrogation in favor of Landlord, its employees, Lenders and any property manager or partners.

10.4 Form of Policies. The minimum limits of policies of insurance required of Tenant under this Lease shall in no event limit the liability of Tenant under this Lease. Such insurance shall (i) name Landlord, its subsidiaries and affiliates, its property manager (if any) and any other party the Landlord so specifies, as an additional insured on the liability insurance, including Landlord’s managing agent, if any; (ii) be issued by an insurance company having a rating of not less than A-:VII in Best’s Insurance Guide or which is otherwise acceptable to Landlord and authorized to do business in the State of California; and (iv) be primary insurance as to all claims thereunder and provide that any insurance carried by Landlord is excess and is non-contributing with any insurance required of Tenant. Tenant shall not cause said insurance to be canceled or coverage changed unless thirty (30) days’ prior written notice shall have been given to Landlord and any mortgagee of Landlord (unless such cancellation is the result of non-payment of premiums, in which case note less than five (5) days’ notice shall be provided). Tenant shall deliver said policy or policies or certificates thereof to Landlord on or before the Lease Commencement Date and at least ten (10) days before the expiration dates thereof. In the event Tenant shall fail to procure such insurance, or to deliver such policies or certificate, Landlord may, at its option, procure such policies for the account of Tenant, and the cost thereof shall be paid to Landlord within five (5) days after delivery to Tenant of bills therefor.

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10.5 Subrogation. Landlord and Tenant hereby agree to look solely to, and seek recovery only from, their respective insurance carriers in the event of a property or business interruption loss to the extent that such coverage is agreed to be provided hereunder, notwithstanding the negligence of either party. Notwithstanding anything to the contrary in this Lease, the parties each hereby waive all rights and claims against each other for such losses, and waive all rights of subrogation of their respective insurers. The parties agree that their respective insurance policies do now, or shall, contain the waiver of subrogation.

10.6 Additional Insurance Obligations. Tenant shall carry and maintain during the entire Lease Term, at Tenant’s sole cost and expense, increased amounts of the insurance required to be carried by Tenant pursuant to this Article 10 and such other reasonable types of insurance coverage and in such reasonable amounts covering the Premises and Tenant’s operations therein, as may be reasonably requested by Landlord or Landlord’s lender, but in no event in excess of the amounts and types of insurance then being required by landlords of buildings comparable to and in the vicinity of the Building.

10.7 Construction Period: The term “Construction Period” shall mean the period from the date of this Lease to the date that Landlord completes construction of the Landlord’s Work (including any “Additional Base Building Items”, as defined in Section 3(f) of the Tenant Work Letter), and Common Areas, regardless of the occurrence of any Tenant Delay and without regard to the effect of any provision of this Lease pursuant to which the Premises are deemed to be Ready for Occupancy in advance of its actual occurrence. Notwithstanding any provision of this Lease to the contrary (including Exhibit B), during the Construction Period only, the following provisions shall be applicable:

10.7.1 with respect to any indemnity obligation of Tenant arising at any time during the Construction Period only, (A) the term “Landlord Parties” shall mean and shall be limited to HCP Oyster Point III LLC, a Delaware limited liability company (or any entity that that succeeds to HCP Oyster Point III LLC’s interest as Landlord under the Lease) and shall not include any other person or entity; provided, however, that Landlord may include in any claim owed by Tenant to it any amount which Landlord shall pay or be obligated to indemnify any other person or entity, and (B) any indemnity obligation shall be limited to losses caused by, or arising as a result of any act or failure to act of, Tenant or Tenant’s employees, agents or contractors; and

10.7.2 during the Construction Period only, Tenant’s liability under this Lease for Tenant’s actions or failures to act under the Lease during the Construction Period, including, without limitation, (A) Tenant’s indemnity obligations, plus (B) Base Rent and Additional Rent (as a consequence of Tenant Delay), plus (C) any and all other costs payable to Landlord or otherwise payable by Tenant under this Lease, which amount shall calculated to include (i) the accreted value of any payments previously made by Tenant plus (ii) the present value of the maximum amount that Tenant could be required to pay as of that point in time (whether or not construction is completed) discounted at Tenant’s incremental borrowing rate used to classify the Lease under ASC 840 (FAS 13), shall be limited to 89.9% of Landlord’s Project Costs determined as of the date of Landlord’s claim for such amount owed by Tenant. As used herein, “Landlord’s Project Costs” shall mean the amount capitalized in the Project by Landlord in accordance with GAAP, plus other costs related to the Project (including related site improvements and other Project costs) paid by Landlord to third parties other than lenders or owners of Landlord (excluding land acquisition costs and “Force Majeure Costs,” as that term is defined below, but including land carrying costs, such as interest or ground rent incurred during the Construction Period, and including all other costs incurred by Landlord in connection with the development and construction of the Project);

10.7.3 “Force Majeure Costs” means the sum of (a) all costs and expenses that are incurred because the Building is damaged by a fire or other casualty event (including capitalized interest on such costs and expenses), less the amount of all insurance proceeds applied to restore the Building, and (b) any loss in fair market value of the Premises to the extent the same are not restored following a fire or other casualty event; and

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10.7.4 the provisions of Section 21.1(H) of the Lease shall not apply during the Construction Period.

10.8 For the avoidance of doubt, Landlord and Tenant agree that:

10.8.1 no claim by Landlord for Tenant’s repudiation of this Lease at any time shall be limited under this section; and

10.8.2 for any claim other than under Section 10.8.1 above, if during the Construction Period Landlord makes any claim for any anticipatory breach by Tenant of any obligation under this Lease owed to Landlord for any period after the Construction Period and the amount payable by Tenant for such claim is limited by the provisions of Section 10.7.2 above, the entire amount (to the extent not theretofore paid) shall be payable promptly after the Construction Period; and

10.8.3 following the end of the Construction Period, the terms of this Section 10.7 shall be of no further force or effect.

11. DAMAGE AND DESTRUCTION.

11.1 Repair of Damage to Premises by Landlord. Tenant shall promptly notify Landlord of any damage to the Premises resulting from fire or any other casualty. If the Premises or any Common Areas serving or providing access to the Premises shall be damaged by fire or other casualty, Landlord shall promptly and diligently, subject to reasonable delays for insurance adjustment or other matters beyond Landlord’s reasonable control, and subject to all other terms of this Article 11, restore the Premises and such Common Areas. Such restoration shall be to substantially the same condition of the Premises and the Common Areas prior to the casualty, except for modifications required by zoning and building codes and other laws or any other modifications to the Common Areas deemed desirable by Landlord, which are consistent with the character of the Project, provided that access to the Premises shall not be materially impaired. Landlord shall not be liable for any inconvenience or annoyance to Tenant or its visitors, or injury to Tenant’s business resulting in any way from such damage or the repair thereof; provided however, that if such fire or other casualty shall have damaged the Premises or Common Areas necessary to Tenant’s occupancy, and the damaged portions of the Premises are not occupied by Tenant as a result thereof, then during the time and to the extent the Premises are unfit for occupancy, the Rent shall be abated in proportion to the ratio that the amount of rentable square feet of the Premises which is unfit for occupancy for the purposes permitted under this Lease bears to the total rentable square feet of the Premises.

11.2 Landlord’s Option to Repair. Notwithstanding the terms of Section 11.1 of this Lease, Landlord may elect not to rebuild and/or restore the Premises, Building and/or Project, and instead terminate this Lease, by notifying Tenant in writing of such termination within sixty (60) days after the date of discovery of the damage, such notice to include a termination date giving Tenant sixty (60) days to vacate the Premises, but Landlord may so elect only if the Building shall be damaged by fire or other casualty or cause, and one or more of the following conditions is present: (i) in Landlord’s reasonable judgment, repairs cannot reasonably be completed within one (1) year after the date of discovery of the damage (when such repairs are made without the payment of overtime or other premiums); (ii) the damage is due to a risk that Landlord is not required to insure under this Lease, and the cost of restoration exceed five percent (5%) of the replacement cost of the Building (unless Tenant agrees to pay any uninsured amount in excess of such five percent (5%)); or (iii) the damage occurs during the last twelve

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(12) months of the Lease Term and will take more than sixty (60) days to restore; provided, however, that if Landlord does not elect to terminate this Lease pursuant to Landlord’s termination right as provided above, and the repairs cannot, in the reasonable opinion of Landlord, be completed within eight (8) months days after the date of discovery of the damage (or are not in fact completed within nine (9) months after the date of discovery of the damage), Tenant may elect, no earlier than sixty (60) days after the date of the damage and not later than ninety (90) days after the date of such damage, or within thirty (30) days after such repairs are not timely completed, to terminate this Lease by written notice to Landlord effective as of the date specified in the notice, which date shall not be less than thirty (30) days nor more than sixty (60) days after the date such notice is given by Tenant.

11.3 Waiver of Statutory Provisions. The provisions of this Lease, including this Article 11, constitute an express agreement between Landlord and Tenant with respect to any and all damage to, or destruction of, all or any part of the Premises, the Building or the Project, and any statute or regulation of the State of California, including, without limitation, Sections 1932(2) and 1933(4) of the California Civil Code, with respect to any rights or obligations concerning damage or destruction in the absence of an express agreement between the parties, and any other statute or regulation, now or hereafter in effect, shall have no application to this Lease or any damage or destruction to all or any part of the Premises, the Building or the Project.

12. NONWAIVER. No provision of this Lease shall be deemed waived by either party hereto unless expressly waived in a writing signed thereby. The waiver by either party hereto of any breach of any term, covenant or condition herein contained shall not be deemed to be a waiver of any subsequent breach of same or any other term, covenant or condition herein contained. The subsequent acceptance of Rent hereunder by Landlord shall not be deemed to be a waiver of any preceding breach by Tenant of any term, covenant or condition of this Lease, other than the failure of Tenant to pay the particular Rent so accepted, regardless of Landlord’s knowledge of such preceding breach at the time of acceptance of such Rent. No acceptance of a lesser amount than the Rent herein stipulated shall be deemed a waiver of Landlord’s right to receive the full amount due, nor shall any endorsement or statement on any check or payment or any letter accompanying such check or payment be deemed an accord and satisfaction, and Landlord may accept such check or payment without prejudice to Landlord’s right to recover the full amount due. No receipt of monies by Landlord from Tenant after the termination of this Lease shall in any way alter the length of the Lease Term or of Tenant’s right of possession hereunder, or after the giving of any notice shall reinstate, continue or extend the Lease Term or affect any notice given Tenant prior to the receipt of such monies, it being agreed that after the service of notice or the commencement of a suit, or after final judgment for possession of the Premises, Landlord may receive and collect any Rent due, and the payment of said Rent shall not waive or affect said notice, suit or judgment.

13. CONDEMNATION. If the whole or any part of the Premises shall be taken by power of eminent domain or condemned by any competent authority for any public or quasi-public use or purpose, or if any adjacent property or street shall be so taken or condemned, or reconfigured or vacated by such authority in such manner as to require the use or reconstruction of any part of the Premises, or if Landlord shall grant a deed or other instrument in lieu of such taking by eminent domain or condemnation, Landlord shall have the option to terminate this Lease effective as of the date possession is required to be surrendered to the authority. Tenant shall not because of such taking assert any claim against Landlord or the authority for any compensation because of such taking and Landlord shall be entitled to the entire award or payment in connection therewith, except that Tenant shall have the right to file any separate claim available to Tenant for any taking of Tenant’s personal property and fixtures belonging to Tenant and removable by Tenant upon expiration of the Lease Term pursuant to the terms of this Lease, for moving expenses, for the unamortized value of any improvements paid for by Tenant and for the Lease “bonus value”, so long as such claims are payable separately to Tenant. All Rent shall be apportioned as of the date of such termination. If any part of the Premises shall be taken, and this Lease shall not be so

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terminated, the Rent shall be proportionately abated. Tenant hereby waives any and all rights it might otherwise have pursuant to Section 1265.130 of The California Code of Civil Procedure. Notwithstanding anything to the contrary contained in this Article 13, in the event of a temporary taking of all or any portion of the Premises for a period of one hundred and eighty (180) days or less, then this Lease shall not terminate but the Base Rent and the Additional Rent shall be abated for the period of such taking in proportion to the ratio that the amount of rentable square feet of the Premises taken bears to the total rentable square feet of the Premises. Landlord shall be entitled to receive the entire award made in connection with any such temporary taking.

14. ASSIGNMENT AND SUBLETTING.

14.1 Transfers. Tenant shall not, without the prior written consent of Landlord, assign, mortgage, pledge, hypothecate, encumber, or permit any lien to attach to, or otherwise transfer, this Lease or any interest hereunder, permit any assignment, or other transfer of this Lease or any interest hereunder by operation of law, sublet the Premises or any part thereof, or enter into any license or concession agreements or otherwise permit the occupancy or use of the Premises or any part thereof by any persons other than Tenant and its employees and contractors (all of the foregoing are hereinafter sometimes referred to collectively as “Transfers” and any person to whom any Transfer is made or sought to be made is hereinafter sometimes referred to as a “Transferee”). If Tenant desires Landlord’s consent to any Transfer, Tenant shall notify Landlord in writing, which notice (the “Transfer Notice”) shall include (i) the proposed effective date of the Transfer, which shall not be less than thirty (30) days nor more than one hundred eighty (180) days after the date of delivery of the Transfer Notice, (ii) a description of the portion of the Premises to be transferred (the “Subject Space”), (iii) all of the terms of the proposed Transfer and the consideration therefor, including calculation of the “Transfer Premium”, as that term is defined in Section 14.3 below, in connection with such Transfer, the name and address of the proposed Transferee, and a copy of all existing executed and/or proposed documentation pertaining to the proposed Transfer, and (iv) current financial statements of the proposed Transferee certified by an officer, partner or owner thereof, and any other information reasonably required by Landlord which will enable Landlord to determine the financial responsibility, character, and reputation of the proposed Transferee, nature of such Transferee’s business and proposed use of the Subject Space. Any Transfer made without Landlord’s prior written consent shall, at Landlord’s option, be null, void and of no effect, and shall, at Landlord’s option, constitute a default by Tenant under this Lease. Whether or not Landlord consents to any proposed Transfer, Tenant shall pay Landlord’s reasonable review and processing fees, as well as any reasonable professional fees (including, without limitation, attorneys’, accountants’, architects’, engineers’ and consultants’ fees) incurred by Landlord (not to exceed $3,500 in the aggregate for any particular Transfer), within thirty (30) days after written request by Landlord.

14.2 Landlord’s Consent. Landlord shall not unreasonably withhold or delay its consent to any proposed Transfer of the Subject Space to the Transferee on the terms specified in the Transfer Notice. Without limitation as to other reasonable grounds for withholding consent, the parties hereby agree that it shall be reasonable under this Lease and under any applicable law for Landlord to withhold consent to any proposed Transfer where one or more of the following apply:

14.2.1 The Transferee is of a character or reputation or engaged in a business which is not consistent with the quality of the Building or the Project;

14.2.2 The Transferee is either a governmental agency or instrumentality thereof;

14.2.3 The Transferee is not a party of reasonable financial worth and/or financial stability in light of the responsibilities to be undertaken in connection with the Transfer on the date consent is requested; or

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14.2.4 The proposed Transfer would cause a violation of another lease for space in the Project, or would give an occupant of the Project a right to cancel its lease.

If Landlord consents to any Transfer pursuant to the terms of this Section 14.2 (and does not exercise any recapture rights Landlord may have under Section 14.4 of this Lease), Tenant may within six (6) months after Landlord’s consent, but not later than the expiration of said six-month period, enter into such Transfer of the Premises or portion thereof, upon substantially the same terms and conditions as are set forth in the Transfer Notice furnished by Tenant to Landlord pursuant to Section 14.1 of this Lease, provided that if there are any changes in the terms and conditions from those specified in the Transfer Notice such that Landlord would initially have been entitled to refuse its consent to such Transfer under this Section 14.2, Tenant shall again submit the Transfer to Landlord for its approval and other action under this Article 14 (including Landlord’s right of recapture, if any, under Section 14.4 of this Lease). Notwithstanding anything to the contrary in this Lease, if Tenant or any proposed Transferee claims that Landlord has unreasonably withheld or delayed its consent under Section 14.2 or otherwise has breached or acted unreasonably under this Article 14, their sole remedies shall be a suit for contract damages (other than damages for injury to, or interference with, Tenant’s business including, without limitation, loss of profits, however occurring) or declaratory judgment and an injunction for the relief sought, and Tenant hereby waives all other remedies, including, without limitation, any right at law or equity to terminate this Lease, on its own behalf and, to the extent permitted under all applicable laws, on behalf of the proposed Transferee.

14.3 Transfer Premium. If Landlord consents to a Transfer, as a condition thereto which the parties hereby agree is reasonable, Tenant shall pay to Landlord fifty percent (50%) of any “Transfer Premium,” as that term is defined in this Section 14.3, received by Tenant from such Transferee. “Transfer Premium” shall mean all rent, additional rent or other consideration payable by such Transferee in connection with the Transfer in excess of the Rent and Additional Rent payable by Tenant under this Lease during the term of the Transfer on a per rentable square foot basis if less than all of the Premises is transferred, and after deduction of (i) any costs of improvements made to the Subject Space in connection with such Transfer, (ii) brokerage commissions paid in connection with such Transfer, and (iii) reasonable legal fees incurred in connection with such Transfer. “Transfer Premium” shall also include, but not be limited to, key money, bonus money or other cash consideration paid by Transferee to Tenant in connection with such Transfer, and any payment in excess of fair market value for services rendered by Tenant to Transferee or for assets, fixtures, inventory, equipment, or furniture transferred by Tenant to Transferee in connection with such Transfer. The determination of the amount of Landlord’s applicable share of the Transfer Premium shall be made on a monthly basis as rent or other consideration is received by Tenant under the Transfer.

14.4 Landlord’s Option as to Subject Space. Notwithstanding anything to the contrary contained in this Article 14, in the event Tenant contemplates a Transfer other than to a Permitted Transferee which, together with all prior Transfers then remaining in effect, would cause fifty percent (50%) or more of the Premises to be Transferred for more than fifty percent (50%) of the then remaining Lease Term (taking into account any extension of the Lease Term which has irrevocably exercised by Tenant), Tenant shall give Landlord notice (the “Intention to Transfer Notice”) of such contemplated Transfer (whether or not the contemplated Transferee or the terms of such contemplated Transfer have been determined). The Intention to Transfer Notice shall specify the portion of and amount of rentable square feet of the Premises which Tenant intends to Transfer in the subject Transfer (the “Contemplated Transfer Space”), the contemplated date of commencement of the Contemplated Transfer (the “Contemplated Effective Date”), and the contemplated length of the term of such contemplated Transfer. Thereafter, Landlord shall have the option, by giving written notice to Tenant within thirty (30) days after receipt of any Intention to Transfer Notice, to recapture the Contemplated Transfer Space. Such recapture shall cancel and terminate this Lease with respect to such Contemplated Transfer Space as of

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the Contemplated Effective Date. In the event of a recapture by Landlord, if this Lease shall be canceled with respect to less than the entire Premises, the Rent reserved herein shall be prorated on the basis of the number of rentable square feet retained by Tenant in proportion to the number of rentable square feet contained in the Premises, and this Lease as so amended shall continue thereafter in full force and effect, and upon request of either party, the parties shall execute written confirmation of the same. If Landlord declines, or fails to elect in a timely manner, to recapture such Contemplated Transfer Space under this Section 14.4, then, subject to the other terms of this Article 14, for a period of nine (9) months (the “Nine Month Period”) commencing on the last day of such thirty (30) day period, Landlord shall not have any right to recapture the Contemplated Transfer Space with respect to any Transfer made during the Nine Month Period, provided that any such Transfer is substantially on the terms set forth in the Intention to Transfer Notice, and provided further that any such Transfer shall be subject to the remaining terms of this Article 14. If such a Transfer is not so consummated within the Nine Month Period (or if a Transfer is so consummated, then upon the expiration of the term of any Transfer of such Contemplated Transfer Space consummated within such Nine Month Period), Tenant shall again be required to submit a new Intention to Transfer Notice to Landlord with respect any contemplated Transfer, as provided above in this Section 14.4. Tenant shall not be required to provide a separate Intention to Transfer Notice and Tenant’s request for Landlord’s consent to a Transfer shall satisfy Tenant’s obligations in this Section 14.4.

14.5 Effect of Transfer. If Landlord consents to a Transfer, (i) the terms and conditions of this Lease shall in no way be deemed to have been waived or modified, (ii) such consent shall not be deemed consent to any further Transfer by either Tenant or a Transferee, (iii) Tenant shall deliver to Landlord, promptly after execution, an original executed copy of all documentation pertaining to the Transfer in form reasonably acceptable to Landlord, (iv) Tenant shall furnish upon Landlord’s request a complete statement, certified by an independent certified public accountant, or Tenant’s chief financial officer, setting forth in detail the computation of any Transfer Premium Tenant has derived and shall derive from such Transfer, and (v) no Transfer relating to this Lease or agreement entered into with respect thereto, whether with or without Landlord’s consent, shall relieve Tenant or any guarantor of the Lease from any liability under this Lease, including, without limitation, in connection with the Subject Space. Landlord or its authorized representatives shall have the right at all reasonable times to audit the books, records and papers of Tenant relating to any Transfer, and shall have the right to make copies thereof. If the Transfer Premium respecting any Transfer shall be found understated, Tenant shall, within thirty (30) days after demand, pay the deficiency, and if understated by more than two percent (2%), Tenant shall pay Landlord’s costs of such audit.

14.6 Additional Transfers. For purposes of this Lease, the term “Transfer” shall also include if Tenant is a partnership, the withdrawal or change, voluntary, involuntary or by operation of law, of fifty percent (50%) or more of the partners, or transfer of fifty percent (50%) or more of partnership interests, within a twelve (12)-month period, or the dissolution of the partnership without immediate reconstitution thereof.

14.7 Occurrence of Default. Any Transfer hereunder shall be subordinate and subject to the provisions of this Lease, and if this Lease shall be terminated during the term of any Transfer, Landlord shall have the right to: (i) treat such Transfer as cancelled and repossess the Subject Space by any lawful means, or (ii) require that such Transferee attorn to and recognize Landlord as its landlord under any such Transfer. If Tenant shall be in default under this Lease, Landlord is hereby irrevocably authorized, as Tenant’s agent and attorney-in-fact, to direct any Transferee to make all payments under or in connection with the Transfer directly to Landlord (which Landlord shall apply towards Tenant’s obligations under this Lease) until such default is cured. Such Transferee shall rely on any representation by Landlord that Tenant is in default hereunder, without any need for confirmation thereof by Tenant. Upon any assignment, the assignee shall assume in writing all obligations and covenants of Tenant thereafter to be

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performed or observed under this Lease. No collection or acceptance of rent by Landlord from any Transferee shall be deemed a waiver of any provision of this Article 14 or the approval of any Transferee or a release of Tenant from any obligation under this Lease, whether theretofore or thereafter accruing. In no event shall Landlord’s enforcement of any provision of this Lease against any Transferee be deemed a waiver of Landlord’s right to enforce any term of this Lease against Tenant or any other person. If Tenant’s obligations hereunder have been guaranteed, Landlord’s consent to any Transfer shall not be effective unless the guarantor also consents to such Transfer.

14.8 Non-Transfers. Notwithstanding anything to the contrary contained in this Article 14, (i) an assignment or subletting of all or a portion of the Premises to an affiliate of Tenant (an entity which is controlled by, controls, or is under common control with, Tenant), (ii) an assignment of the Premises to an entity which acquires all or substantially all of the assets or interests (partnership, stock or other) of Tenant, (iii) an assignment of the Premises to an entity which is the resulting entity of a merger or consolidation of Tenant with another entity, or (iv) a sale of corporate shares of capital stock in Tenant in connection with an initial public offering of Tenant’s stock on a nationally-recognized stock exchange (collectively, a “Permitted Transferee”), shall not be deemed a Transfer under this Article 14, provided that (A) Tenant notifies Landlord of any such assignment or sublease and promptly supplies Landlord with any documents or information requested by Landlord regarding such assignment or sublease or such affiliate, (B) such assignment or sublease is not a subterfuge by Tenant to avoid its obligations under this Lease, (C) such Permitted Transferee shall be of a character and reputation consistent with the quality of the Building, and (D) such Permitted Transferee described in subpart (ii) or (iii) above shall have a tangible net worth (not including goodwill as an asset) computed in accordance with generally accepted accounting principles (“Net Worth”) at least equal to the Net Worth of Tenant on the day immediately preceding the effective date of such assignment or sublease. An assignee of Tenant’s entire interest that is also a Permitted Transferee may also be known as a “Permitted Assignee”. “Control,” as used in this Section 14.8, shall mean the ownership, directly or indirectly, of at least fifty-one percent (51%) of the voting securities of, or possession of the right to vote, in the ordinary direction of its affairs, of at least fifty-one percent (51%) of the voting interest in, any person or entity. No such permitted assignment or subletting shall serve to release Tenant from any of its obligations under this Lease.

15. SURRENDER OF PREMISES; OWNERSHIP AND REMOVAL OF TRADE FIXTURES.

15.1 Surrender of Premises. No act or thing done by Landlord or any agent or employee of Landlord during the Lease Term shall be deemed to constitute an acceptance by Landlord of a surrender of the Premises unless such intent is specifically acknowledged in writing by Landlord. The delivery of keys to the Premises to Landlord or any agent or employee of Landlord shall not constitute a surrender of the Premises or effect a termination of this Lease, whether or not the keys are thereafter retained by Landlord, and notwithstanding such delivery Tenant shall be entitled to the return of such keys at any reasonable time upon request until this Lease shall have been properly terminated. The voluntary or other surrender of this Lease by Tenant, whether accepted by Landlord or not, or a mutual termination hereof, shall not work a merger, and at the option of Landlord shall operate as an assignment to Landlord of all subleases or subtenancies affecting the Premises or terminate any or all such sublessees or subtenancies.

15.2 Removal of Tenant Property by Tenant. Upon the expiration of the Lease Term, or upon any earlier termination of this Lease, Tenant shall, subject to the provisions of this Article 15, quit and surrender possession of the Premises to Landlord in as good order and condition as when Tenant took possession and as thereafter improved by Landlord and/or Tenant, reasonable wear and tear, damage caused by casualty, repairs required as a result of condemnation, and repairs which are specifically made the responsibility of Landlord hereunder excepted. Upon such expiration or termination, Tenant shall, without expense to Landlord, remove or cause to be removed from the Premises all debris and rubbish, and such items of furniture, equipment, free-standing cabinet work, movable partitions (but not

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demountable walls) and other articles of personal property owned by Tenant or installed or placed by Tenant at its expense in the Premises, and such similar articles of any other persons claiming under Tenant, as Landlord may, in its sole discretion, require to be removed, and Tenant shall repair at its own expense all damage to the Premises and Building resulting from such removal.

15.3 Environmental Assessment. In connection with its surrender of the Premises, Tenant shall submit to Landlord, at least fifteen (15) days prior to the expiration date of this Lease (or in the event of an earlier termination of this Lease, as soon as reasonably possible following such termination), an environmental Assessment of the Premises by a competent and experienced environmental engineer or engineering firm reasonably satisfactory to Landlord (pursuant to a contract approved by Landlord and providing that Landlord can rely on the Environmental Assessment). If such Environmental Assessment reveals that remediation or Clean-up is required under any Environmental Laws that Tenant is responsible for under this Lease, Tenant shall submit a remediation plan prepared by a recognized environmental consultant and shall be responsible for all costs of remediation and Clean-up, as more particularly provided in Section 5.3, above.

15.4 Condition of the Building and Premises Upon Surrender. In addition to the above requirements of this Article 15, upon the expiration of the Lease Term, or upon any earlier termination of this Lease, Tenant shall, surrender the Premises and Building with Tenant having complied with all of Tenant’s obligations under this Lease, including those relating to improvement, repair, maintenance, compliance with law, testing and other related obligations of Tenant set forth in Article 7 of this Lease. In the event that the Building and Premises shall be surrendered in a condition which does not comply with the terms of this Section 15.4, because Tenant failed to comply with its obligations set forth in Lease, then following thirty (30) days’ notice to Tenant, during which thirty (30) day period Tenant shall have the right to cure such noncompliance, Landlord shall be entitled to expend all reasonable costs in order to cause the same to comply with the required condition upon surrender and Tenant shall immediately reimburse Landlord for all such costs upon notice and, commencing on the later of the termination of this Lease and three (3) business days after Landlord’s delivery of notice of such failure and that it elects to treat such failure as a holdover, Tenant shall be deemed during the period that Tenant or Landlord, as the case may be, perform obligations relating to the Surrender Improvements to be in holdover under Article 16 of this Lease.

16. HOLDING OVER. If Tenant holds over after the expiration of the Lease Term or earlier termination thereof, with the express or implied consent of Landlord, such tenancy shall be from month-to-month only, and shall not constitute a renewal hereof or an extension for any further term. If Tenant holds over after the expiration of the Lease Term of earlier termination thereof, without the express or implied consent of Landlord, such tenancy shall be deemed to be a tenancy by sufferance only, and shall not constitute a renewal hereof or an extension for any further term. In either case, Base Rent shall be payable at a monthly rate equal to one hundred fifty percent (150%) of the Base Rent applicable during the last rental period of the Lease Term under this Lease. Such month-to-month tenancy or tenancy by sufferance, as the case may be, shall be subject to every other applicable term, covenant and agreement contained herein. Nothing contained in this Article 16 shall be construed as consent by Landlord to any holding over by Tenant, and Landlord expressly reserves the right to require Tenant to surrender possession of the Premises to Landlord as provided in this Lease upon the expiration or other termination of this Lease. The provisions of this Article 16 shall not be deemed to limit or constitute a waiver of any other rights or remedies of Landlord provided herein or at law. If Tenant fails to surrender the Premises upon the termination or expiration of this Lease, in addition to any other liabilities to Landlord accruing therefrom, Tenant shall protect, defend, indemnify and hold Landlord harmless from all loss, costs (including reasonable attorneys’ fees) and liability resulting from such failure, including, without limiting the generality of the foregoing, any claims made by any succeeding tenant founded upon such failure to surrender and any lost profits to Landlord resulting therefrom.

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17. ESTOPPEL CERTIFICATES. Within ten (10) business days following a request in writing by Landlord, Tenant shall execute, acknowledge and deliver to Landlord an estoppel certificate, which, as submitted by Landlord, shall be substantially in the form of Exhibit D, attached hereto (or such other form as may be reasonably required by any prospective mortgagee or purchaser of the Project, or any portion thereof), indicating therein any exceptions thereto that may exist at that time, and shall also contain any other information reasonably requested by Landlord or Landlord’s mortgagee or prospective mortgagee. Any such certificate may be relied upon by any prospective mortgagee or purchaser of all or any portion of the Project. Tenant shall execute and deliver whatever other instruments may be reasonably required for such purposes. At any time during the Lease Term, in connection with a sale or financing of the Building by Landlord, Landlord may require Tenant to provide Landlord with its most recent annual financial statement and annual financial statements of the preceding two (2) years. Such statements shall be prepared in accordance with generally accepted accounting principles and, if such is the normal practice of Tenant, shall be audited by an independent certified public accountant. Landlord shall hold such statements confidential. Failure of Tenant to timely execute, acknowledge and deliver such estoppel certificate or other instruments shall constitute an acceptance of the Premises and an acknowledgment by Tenant that statements included in the estoppel certificate are true and correct, without exception.

18. SUBORDINATION. Landlord hereby represents and warrants to Tenant that the Project is not currently subject to any ground lease, or to the lien of any mortgage or deed of trust. This Lease shall be subject and subordinate to all future ground or underlying leases of the Building or Project and to the lien of any mortgage, trust deed or other encumbrances now or hereafter in force against the Building or Project or any part thereof, if any, and to all renewals, extensions, modifications, consolidations and replacements thereof, and to all advances made or hereafter to be made upon the security of such mortgages or trust deeds, unless the holders of such mortgages, trust deeds or other encumbrances, or the lessors under such ground lease or underlying leases, require in writing that this Lease be superior thereto. The subordination of this Lease to any such future ground or underlying leases of the Building or Project or to the lien of any mortgage, trust deed or other encumbrances, shall be subject to Tenant’s receipt of a commercially reasonable subordination, non-disturbance, and attornment agreement in favor of Tenant. Tenant covenants and agrees in the event any proceedings are brought for the foreclosure of any such mortgage or deed in lieu thereof (or if any ground lease is terminated), to attorn, without any deductions or set-offs whatsoever, to the lienholder or purchaser or any successors thereto upon any such foreclosure sale or deed in lieu thereof (or to the ground lessor), if so requested to do so by such purchaser or lienholder or ground lessor, and to recognize such purchaser or lienholder or ground lessor as the lessor under this Lease, provided such lienholder or purchaser or ground lessor shall agree to accept this Lease and not disturb Tenant’s occupancy, so long as Tenant timely pays the rent and observes and performs the terms, covenants and conditions of this Lease to be observed and performed by Tenant. Landlord’s interest herein may be assigned as security at any time to any lienholder. Tenant shall, within ten (10) days of request by Landlord, execute such further instruments or assurances as Landlord may reasonably deem necessary to evidence or confirm the subordination or superiority of this Lease to any such mortgages, trust deeds, ground leases or underlying leases. Tenant waives the provisions of any current or future statute, rule or law which may give or purport to give Tenant any right or election to terminate or otherwise adversely affect this Lease and the obligations of the Tenant hereunder in the event of any foreclosure proceeding or sale.

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19. DEFAULTS; REMEDIES.

19.1 Events of Default. The occurrence of any of the following shall constitute a default of this Lease by Tenant:

19.1.1 Any failure by Tenant to pay any Rent or any other charge required to be paid under this Lease, or any part thereof, when due unless such failure is cured within five (5) business days after notice; or

19.1.2 Except where a specific time period is otherwise set forth for Tenant’s performance in this Lease, in which event the failure to perform by Tenant within such time period shall be a default by Tenant under this Section 19.1.2, any failure by Tenant to observe or perform any other provision, covenant or condition of this Lease to be observed or performed by Tenant where such failure continues for thirty (30) days after written notice thereof from Landlord to Tenant; provided that if the nature of such default is such that the same cannot reasonably be cured within a thirty (30) day period, Tenant shall not be deemed to be in default if it diligently commences such cure within such period and thereafter diligently proceeds to rectify and cure such default; or

19.1.3 Abandonment or vacation of all or a substantial portion of the Premises by Tenant while Tenant is in default under the Lease; or

19.1.4 The failure by Tenant to observe or perform according to the provisions of Articles 5, 14, 17 or 18 of this Lease where such failure continues for more than five (5) business days after notice from Landlord.

19.2 Remedies Upon Default. Upon the occurrence of any event of default by Tenant, Landlord shall have, in addition to any other remedies available to Landlord at law or in equity (all of which remedies shall be distinct, separate and cumulative), the option to pursue any one or more of the following remedies, each and all of which shall be cumulative and nonexclusive, without any notice or demand whatsoever.

19.2.1 Terminate this Lease, in which event Tenant shall immediately surrender the Premises to Landlord, and if Tenant fails to do so, Landlord may, without prejudice to any other remedy which it may have for possession or arrearages in rent, enter upon and take possession of the Premises and expel or remove Tenant and any other person who may be occupying the Premises or any part thereof, without being liable for prosecution or any claim or damages therefor; and Landlord may recover from Tenant the following:

(i) The worth at the time of award of the unpaid rent which has been earned at the time of such termination; plus

(ii) The worth at the time of award of the amount by which the unpaid rent which would have been earned after termination until the time of award exceeds the amount of such rental loss that Tenant proves could have been reasonably avoided; plus

(iii) The worth at the time of award of the amount by which the unpaid rent for the balance of the Lease Term after the time of award exceeds the amount of such rental loss that Tenant proves could have been reasonably avoided; plus

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(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, specifically including but not limited to, in each case to the extent allocable to the remaining Lease Term, brokerage commissions and advertising expenses incurred to obtain a new tenant, expenses of remodeling the Premises or any portion thereof for a new tenant, whether for the same or a different use, and any special concessions made to obtain a new tenant; and

(v) At Landlord’s election, such other amounts in addition to or in lieu of the foregoing as may be permitted from time to time by applicable law.

The term “rent” as used in this Section 19.2 shall be deemed to be and to mean all sums of every nature required to be paid by Tenant pursuant to the terms of this Lease, whether to Landlord or to others. As used in Sections 19.2.1(i) and (ii), above, the “worth at the time of award” shall be computed by allowing interest at the rate set forth in Article 25 of this Lease, but in no case greater than the maximum amount of such interest permitted by law. As used in Section 19.2.1(iii) above, the “worth at the time of award” shall be computed by discounting such amount at the discount rate of the Federal Reserve Bank of San Francisco at the time of award plus one percent (1%).

19.2.2 Landlord shall have the remedy described in 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 the right to sublet or assign, subject only to reasonable limitations). Accordingly, if Landlord does not elect to terminate this Lease on account of any default by Tenant, Landlord may, from time to time, without terminating this Lease, enforce all of its rights and remedies under this Lease, including the right to recover all rent as it becomes due.

19.2.3 Landlord shall at all times have the rights and remedies (which shall be cumulative with each other and cumulative and in addition to those rights and remedies available under Sections 19.2.1 and 19.2.2, above, or any law or other provision of this Lease), without prior demand or notice except as required by applicable law, to seek any declaratory, injunctive or other equitable relief, and specifically enforce this Lease, or restrain or enjoin a violation or breach of any provision hereof.

19.3 Subleases of Tenant. If Landlord elects to terminate this Lease on account of any default by Tenant, as set forth in this Article 19, Landlord shall have the right to terminate any and all subleases, licenses, concessions or other consensual arrangements for possession entered into by Tenant and affecting the Premises or may, in Landlord’s sole discretion, succeed to Tenant’s interest in such subleases, licenses, concessions or arrangements. In the event of Landlord’s election to succeed to Tenant’s interest in any such subleases, licenses, concessions or arrangements, Tenant shall, as of the date of notice by Landlord of such election, have no further right to or interest in the rent or other consideration receivable thereunder.

19.4 Efforts to Relet. No re-entry, repairs, maintenance, changes, alterations and additions, appointment of a receiver to protect Landlord’s interests hereunder, or any other action or omission by Landlord shall be construed as an election by Landlord to terminate this Lease or Tenant’s right to possession, or to accept a surrender of the Premises, nor shall same operate to release Tenant in whole or in part from any of Tenant’s obligations hereunder, unless express written notice of such intention is sent by Landlord to Tenant.

20. COVENANT OF QUIET ENJOYMENT. Landlord covenants that Tenant, on paying the Rent, charges for services and other payments herein reserved and on keeping, observing and performing all the other terms, covenants, conditions, provisions and agreements herein contained on the part of Tenant to be kept, observed and performed, shall, during the Lease Term, peaceably and quietly have, hold and enjoy the Premises subject to the terms, covenants, conditions, provisions and agreements hereof without interference by any persons lawfully claiming by or through Landlord. The foregoing covenant is in lieu of any other covenant express or implied.

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21. LETTER OF CREDIT.

21.1 Delivery of Letter of Credit. Tenant shall deliver to Landlord, concurrently with Tenant’s execution of this Lease, an unconditional, clean, irrevocable letter of credit (the “L-C”) in the amount set forth in Section 8 of the Lease Summary (the “L-C Amount”), which L-C shall be issued by a money-center, solvent and nationally recognized bank (a bank which accepts deposits, maintains accounts, has a local San Francisco Bay Area office which will negotiate a letter of credit, and whose deposits are insured by the FDIC) reasonably acceptable to Landlord (such approved, issuing bank being referred to herein as the “Bank”), which Bank must have a rating from Standard and Poors Corporation of A- or better (or any equivalent rating thereto from any successor or substitute rating service selected by Lessor) and a letter of credit issuer rating from Moody’s Investor Service of A3 or better (or any equivalent rating thereto from any successor rating agency thereto)) (collectively, the “Bank’s Credit Rating Threshold”), and which L-C shall be in the form of Exhibit H, attached hereto. Notwithstanding the foregoing, Landlord hereby approves Silicon Valley Bank as the Bank. Tenant shall pay all expenses, points and/or fees incurred by Tenant in obtaining the L-C. The L-C shall (i) be “callable” at sight, irrevocable and unconditional, (ii) be maintained in effect, whether through renewal or extension, for the period commencing on the date of this Lease and continuing until the date (the “L-C Expiration Date”) that is no less than sixty (60) days after the expiration of the Lease Term as the same may be extended, and Tenant shall deliver a new L-C or certificate of renewal or extension to Landlord at least thirty (30) days prior to the expiration of the L-C then held by Landlord, without any action whatsoever on the part of Landlord, (iii) be fully assignable by Landlord, its successors and assigns, (iv) permit partial draws and multiple presentations and drawings, and (v) be otherwise subject to the Uniform Customs and Practices for Documentary Credits (1993-Rev), International Chamber of Commerce Publication #500, or the International Standby Practices-ISP 98, International Chamber of Commerce Publication #590. Landlord, or its then managing agent, shall have the right to draw down an amount up to the face amount of the L-C if any of the following shall have occurred or be applicable: (A) such amount is due to Landlord under the terms and conditions of this Lease, and has not been paid within applicable notice and cure periods (or, if Landlord is prevented by law from providing notice, within the period for payment set forth in the Lease), or (B) Tenant has filed a voluntary petition under the U. S. Bankruptcy Code or any state bankruptcy code (collectively, “Bankruptcy Code”), or (C) an involuntary petition has been filed against Tenant under the Bankruptcy Code that is not dismissed within thirty (30) days, or (D) the Lease has been rejected, or is deemed rejected, under Section 365 of the U.S. Bankruptcy Code, following the filing of a voluntary petition by Tenant under the Bankruptcy Code, or the filing of an involuntary petition against Tenant under the Bankruptcy Code, or (E) the Bank has notified Landlord that the L-C will not be renewed or extended through the L-C Expiration Date, and Tenant has not provided a replacement L-C that satisfies the requirements of this Lease at least thirty (30) days prior to such expiration, or (F) Tenant is placed into receivership or conservatorship, or becomes subject to similar proceedings under Federal or State law, or (G) Tenant executes an assignment for the benefit of creditors, or (H) if (1) any of the Bank’s (other than Silicon Valley Bank) Fitch Ratings (or other comparable ratings to the extent the Fitch Ratings are no longer available) have been reduced below the Bank’s Credit Rating Threshold, or (2) there is otherwise a material adverse change in the financial condition of the Bank, and Tenant has failed to provide Landlord with a replacement letter of credit, conforming in all respects to the requirements of this Article 21 (including, but not limited to, the requirements placed on the issuing Bank more particularly set forth in this Section 21.1 above), in the amount of the applicable L-C Amount, within ten (10) days following Landlord’s written demand therefor (with no other notice or cure or grace period being applicable thereto, notwithstanding anything in this Lease to the contrary) (each of the foregoing being an “L-C Draw Event”). The L-C shall be honored by the Bank regardless of whether Tenant disputes Landlord’s right to draw upon the L-C. In addition, in the event the Bank is placed into receivership or conservatorship by the

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Federal Deposit Insurance Corporation or any successor or similar entity, then, effective as of the date such receivership or conservatorship occurs, said L-C shall be deemed to fail to meet the requirements of this Article 21, and, within ten (10) days following Landlord’s notice to Tenant of such receivership or conservatorship (the “L-C FDIC Replacement Notice”), Tenant shall replace such L-C with a substitute letter of credit from a different issuer (which issuer shall meet or exceed the Bank’s Credit Rating Threshold and shall otherwise be acceptable to Landlord in its reasonable discretion) and that complies in all respects with the requirements of this Article 21. If Tenant fails to replace such L-C with such conforming, substitute letter of credit pursuant to the terms and conditions of this Section 21.1, then, notwithstanding anything in this Lease to the contrary, Landlord shall have the right to declare Tenant in default of this Lease for which there shall be no notice or grace or cure periods being applicable thereto (other than the aforesaid ten (10) day period). Tenant shall be responsible for the payment of any and all Tenant’s and Bank’s costs incurred with the review of any replacement L-C, which replacement is required pursuant to this Section or is otherwise requested by Tenant. In the event of an assignment by Tenant of its interest in the Lease (and irrespective of whether Landlord’s consent is required for such assignment), the acceptance of any replacement or substitute letter of credit by Landlord from the assignee shall be subject to Landlord’s prior written approval, in Landlord’s reasonable discretion, and the actual and reasonable attorney’s fees incurred by Landlord in connection with such determination shall be payable by Tenant to Landlord within ten (10) days of billing.

21.2 Application of L-C. Tenant hereby acknowledges and agrees that Landlord is entering into this Lease in material reliance upon the ability of Landlord to draw upon the L-C upon the occurrence of any L-C Draw Event. In the event of any L-C Draw Event, Landlord may, but without obligation to do so, and without notice to Tenant (except in connection with an L-C Draw Event under Section 21.1(H) above), draw upon the L-C, in part or in whole, in the amount necessary to cure any such L-C Draw Event and/or to compensate Landlord for any and all damages of any kind or nature sustained or which Landlord reasonably estimates that it will sustain resulting from Tenant’s breach or default of the Lease or other L-C Draw Event and/or to compensate Landlord for any and all damages arising out of, or incurred in connection with, the termination of this Lease, including, without limitation, those specifically identified in Section 1951.2 of the California Civil Code. The use, application or retention of the L-C, or any portion thereof, by Landlord shall not prevent Landlord from exercising any other right or remedy provided by this Lease or by any applicable law, it being intended that Landlord shall not first be required to proceed against the L-C, and such L-C shall not operate as a limitation on any recovery to which Landlord may otherwise be entitled. Tenant agrees and acknowledges that (i) the L-C constitutes a separate and independent contract between Landlord and the Bank, (ii) Tenant is not a third party beneficiary of such contract, (iii) Tenant has no property interest whatsoever in the L-C or the proceeds thereof, and (iv) in the event Tenant becomes a debtor under any chapter of the Bankruptcy Code, Tenant is placed into receivership or conservatorship, and/or there is an event of a receivership, conservatorship or a bankruptcy filing by, or on behalf of, Tenant, neither Tenant, any trustee, nor Tenant’s bankruptcy estate shall have any right to restrict or limit Landlord’s claim and/or rights to the L-C and/or the proceeds thereof by application of Section 502(b)(6) of the U. S. Bankruptcy Code or otherwise.

21.3 Maintenance of L-C by Tenant. If, as a result of any drawing by Landlord of all or any portion of the L-C, the amount of the L-C shall be less than the L-C Amount, Tenant shall, within five (5) days thereafter, provide Landlord with additional letter(s) of credit in an amount equal to the deficiency, and any such additional letter(s) of credit shall comply with all of the provisions of this Article 21. Tenant further covenants and warrants that it will neither assign nor encumber the L-C or any part thereof and that neither Landlord 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 L-C expires earlier than the L-C Expiration Date, Landlord will accept a renewal thereof (such renewal letter of credit to be in effect and delivered to Landlord, as applicable, not later than thirty (30) days prior to the expiration of the L-C), which shall be irrevocable and automatically renewable as above provided

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through the L-C Expiration Date upon the same terms as the expiring L-C or such other terms as may be acceptable to Landlord in its sole discretion. If Tenant exercises its option to extend the Lease Term pursuant to Section 2.2 of this Lease then, not later than thirty (30) days prior to the commencement of the Option Term, Tenant shall deliver to Landlord a new L C or certificate of renewal or extension evidencing the L¬C Expiration Date as thirty (30) days after the expiration of the Option Term. However, if the L-C is not timely renewed, or if Tenant fails to maintain the L-C in the amount and in accordance with the terms set forth in this Article 21, Landlord shall have the right to present the L-C to the Bank in accordance with the terms of this Article 21, and the proceeds of the L-C may be applied by Landlord against any Rent payable by Tenant under this Lease that is not paid when due and/or to pay for all losses and damages that Landlord has suffered or that Landlord reasonably estimates that it will suffer as a result of any breach or default by Tenant under this Lease. In the event Landlord elects to exercise its rights as provided above, (I) any unused proceeds shall constitute the property of Landlord (and not Tenant’s property or, in the event of a receivership, conservatorship, or a bankruptcy filing by, or on behalf of, Tenant, property of such receivership, conservatorship or Tenant’s bankruptcy estate) and need not be segregated from Landlord’s other assets, and (II) Landlord agrees to pay to Tenant within thirty (30) days after the L-C Expiration Date the amount of any proceeds of the L-C received by Landlord and not applied against any Rent payable by Tenant under this Lease that was not paid when due or used to pay for any losses and/or damages suffered by Landlord (or reasonably estimated by Landlord that it will suffer) as a result of any breach or default by Tenant under this Lease; provided, however, that if prior to the L-C Expiration Date a voluntary petition is filed by Tenant, or an involuntary petition is filed against Tenant by any of Tenant’s creditors, under the Bankruptcy Code, then Landlord shall not be obligated to make such payment in the amount of the unused L-C proceeds until either all preference issues relating to payments under this Lease have been resolved in such bankruptcy or reorganization case or such bankruptcy or reorganization case has been dismissed. If Landlord draws on the L-C due to Tenant’s failure to timely renew or provide a replacement L-C, such failure shall not be considered a default under this Lease and Landlord shall return such cash proceeds upon Tenant’s presentation of a replacement L-C that satisfies the requirements of this Lease, subject to reasonable satisfaction of any preference risk to Landlord.

21.4 Transfer and Encumbrance. The L-C shall also provide that Landlord may, at any time and without notice to Tenant and without first obtaining Tenant’s consent thereto, transfer (one or more times) all or any portion of its interest in and to the L-C to another party, person or entity, regardless of whether or not such transfer is from or as a part of the assignment by Landlord of its rights and interests in and to this Lease. In the event of a transfer of Landlord’s interest in under this Lease, Landlord shall transfer the L-C, in whole or in part, to the transferee and thereupon Landlord shall, without any further agreement between the parties, be released by Tenant from all liability therefor, and it is agreed that the provisions hereof shall apply to every transfer or assignment of the whole of said L-C to a new landlord. In connection with any such transfer of the L-C by Landlord, Tenant shall, at Tenant’s sole cost and expense, execute and submit to the Bank such applications, documents and instruments as may be necessary to effectuate such transfer and, Tenant shall be responsible for paying the Bank’s transfer and processing fees in connection therewith; provided that, Landlord shall have the right (in its sole discretion), but not the obligation, to pay such fees on behalf of Tenant, in which case Tenant shall reimburse Landlord within ten (10) days after Tenant’s receipt of an invoice from Landlord therefor.

21.5 L-C Not a Security Deposit. Landlord and Tenant (1) acknowledge and agree that in no event or circumstance shall the L-C or any renewal thereof or substitute therefor or any proceeds thereof be deemed to be or treated as a “security deposit” under any law applicable to security deposits in the commercial context, including, but not limited to, Section 1950.7 of the California Civil Code, as such Section now exists or as it may be hereafter amended or succeeded (the “Security Deposit Laws”), (2) acknowledge and agree that the L-C (including any renewal thereof or substitute therefor or any proceeds thereof) is not intended to serve as a security deposit, and the Security Deposit Laws shall have

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no applicability or relevancy thereto, and (3) waive any and all rights, duties and obligations that any such party may now, or in the future will, have relating to or arising from the Security Deposit Laws. Tenant hereby irrevocably waives and relinquishes the provisions of Section 1950.7 of the California Civil Code and any successor statute, and all other provisions of law, now or hereafter in effect, which (x) establish the time frame by which a landlord must refund a security deposit under a lease, and/or (y) provide that a landlord may claim from a security deposit only those sums reasonably necessary to remedy defaults in the payment of rent, to repair damage caused by a tenant or to clean the premises, it being agreed that Landlord may, in addition, claim those sums specified in this Article 21 and/or those sums reasonably necessary to (a) compensate Landlord for any loss or damage caused by Tenant’s breach of this Lease, including any damages Landlord suffers following termination of this Lease, and/or (b) compensate Landlord for any and all damages arising out of, or incurred in connection with, the termination of this Lease, including, without limitation, those specifically identified in Section 1951.2 of the California Civil Code. Tenant agrees not to interfere in any way with any payment to Landlord of the proceeds of the L-C, either prior to or following a “draw” by Landlord of all or any portion of the L¬C, regardless of whether any dispute exists between Tenant and Landlord as to Landlord’s right to draw down all or any portion of the L-C. No condition or term of this Lease shall be deemed to render the L-C conditional and thereby afford the Bank a justification for failing to honor a drawing upon such L-C in a timely manner. Tenant shall not request or instruct the Bank of any L-C to refrain from paying sight draft(s) drawn under such L-C.

21.6 Remedy for Improper Drafts. Tenant’s sole remedy in connection with the improper presentment or payment of sight drafts drawn under any L-C shall be the right to obtain from Landlord a refund of the amount of any sight draft(s) that were improperly presented or the proceeds of which were misapplied, and reasonable actual out-of-pocket attorneys’ fees, provided that at the time of such refund, Tenant increases the amount of such L-C to the amount (if any) then required under the applicable provisions of this Lease. Tenant acknowledges that the presentment of sight drafts drawn under any L-C, or the Bank’s payment of sight drafts drawn under such L-C, could not under any circumstances cause Tenant injury that could not be remedied by an award of money damages, and that the recovery of money damages would be an adequate remedy therefor. In the event Tenant shall be entitled to a refund as aforesaid and Landlord shall fail to make such payment within ten (10) business days after demand, Tenant shall have the right to deduct the amount thereof from the next installment(s) of Base Rent.

22. COMMUNICATIONS AND COMPUTER LINE. Tenant may install, maintain, replace, remove or use any communications or computer wires and cables serving the Premises (collectively, the “Lines”), provided that Tenant shall obtain Landlord’s prior written consent, use an experienced and qualified contractor approved in writing by Landlord, and comply with all of the other provisions of Articles 7 and 8 of this Lease. Tenant shall pay all costs in connection therewith. Landlord reserves the right, upon notice to Tenant prior to the expiration or earlier termination of this Lease, to require that Tenant, at Tenant’s sole cost and expense, remove any Lines located in or serving the Premises prior to the expiration or earlier termination of this Lease.

23. SIGNS.

23.1 Exterior Signage. Subject to Landlord’s prior written approval, which shall not be unreasonably withheld, conditioned or delayed, and provided all signs are in keeping with the quality, design and style of the Building and Project, Tenant, at its sole cost and expense, may install (i) identification signage on the monument sign outside the front entrance to the Building (which monument sign shall be installed by Landlord at its sole cost prior to the Lease Commencement Date), (ii) internal directional and lobby identification signage, (iii) signage in the elevator lobby on the floor containing the Premises, and (iv) one (1) sign on the south elevation of the Building consistent with that certain Master Signage Program dated December 2012 and prepared by DES Architects + Engineers

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(collectively, “Tenant Signage”); provided, however, in no event shall Tenant’s Signage include an “Objectionable Name,” as that term is defined in Section 23.3, of this Lease. All such signage shall be subject to Tenant’s obtaining all required governmental approvals. All permitted signs shall be maintained by Tenant at its expense in a first-class and safe condition and appearance. Upon the expiration or earlier termination of this Lease, Tenant shall remove all of its signs at Tenant’s sole cost and expense. The graphics, materials, color, design, lettering, lighting, size, illumination, specifications and exact location of Tenant’s Signage (collectively, the “Sign Specifications”) shall be subject to the prior written approval of Landlord, which approval shall not be unreasonably withheld, conditioned or delayed, and shall be consistent and compatible with the quality and nature of the Project. Tenant hereby acknowledges that, notwithstanding Landlord’s approval of Tenant’s Signage, Landlord has made no representation or warranty to Tenant with respect to the probability of obtaining all necessary governmental approvals and permits for Tenant’s Signage. In the event Tenant does not receive the necessary governmental approvals and permits for Tenant’s Signage, Tenant’s and Landlord’s rights and obligations under the remaining terms of this Lease shall be unaffected. Except as required by applicable law, Landlord shall not install any other signage on the Building. If Landlord elects to install a multi-tenant identification sign at the entrance to the Project, Tenant shall be entitled to install its name on such sign (subject to availability on a pro-rata basis based on the relative square footages leased by the tenants of the Project), at Tenant’s sole cost and expense.

23.2 Objectionable Name. Tenant’s Signage shall not include a name or logo which relates to an entity which is of a character or reputation, or is associated with a political faction or orientation, which is inconsistent with the quality of the Project, or which would otherwise reasonably offend a landlord of the Comparable Buildings (an “Objectionable Name”). Landlord agrees that “CytomX Therapeutics, Inc.” or “CytomX” is not an Objectionable Name.

23.3 Prohibited Signage and Other Items. Any signs, notices, logos, pictures, names or advertisements which are installed and that have not been separately approved by Landlord may be removed without notice by Landlord at the sole expense of Tenant. Any signs, window coverings, or blinds (even if the same are located behind the Landlord-approved window coverings for the Building), or other items visible from the exterior of the Premises or Building, shall be subject to the prior approval of Landlord, in its sole discretion.

24. COMPLIANCE WITH LAW. Tenant shall not do anything or suffer anything to be done in or about the Premises or the Project which will in any way conflict with any law, statute, ordinance or other governmental rule, regulation or requirement now in force or which may hereafter be enacted or promulgated. At its sole cost and expense, Tenant shall promptly comply with all such governmental measures. Should any standard or regulation now or hereafter be imposed on Landlord or Tenant by a state, federal or local governmental body charged with the establishment, regulation and enforcement of occupational, health or safety standards for employers, employees, landlords or tenants, then Tenant agrees, at its sole cost and expense, to comply promptly with such standards or regulations. Tenant shall be responsible, at its sole cost and expense, to make all alterations to the Building and Premises as are required to comply with the governmental rules, regulations, requirements or standards described in this Article 24. The judgment of any court of competent jurisdiction or the admission of Tenant in any judicial action, regardless of whether Landlord is a party thereto, that Tenant has violated any of said governmental measures, shall be conclusive of that fact as between Landlord and Tenant. Tenant’s obligations under this Article 24 are subject to the limitation in Section 10.2, above.

25. LATE CHARGES. If any installment of Rent or any other sum due from Tenant shall not be received by Landlord or Landlord’s designee within five (5) business days after Tenant’s receipt of written notice from Landlord that said amount is delinquent, then Tenant shall pay to Landlord a late charge equal to five percent (5%) of the overdue amount plus any reasonable attorneys’ fees incurred by Landlord by

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reason of Tenant’s failure to pay Rent and/or other charges when due hereunder. The late charge shall be deemed Additional Rent and the right to require it shall be in addition to all of Landlord’s other rights and remedies hereunder or at law and shall not be construed as liquidated damages or as limiting Landlord’s remedies in any manner. In addition to the late charge described above, any Rent or other amounts owing hereunder which are not paid within ten (10) days after Tenant’s receipt of written notice that said amount is delinquent shall bear interest from the date when due until paid at a rate per annum equal to the lesser of (i) the annual “Bank Prime Loan” rate cited in the Federal Reserve Statistical Release Publication G.13(415), published on the first Tuesday of each calendar month (or such other comparable index as Landlord and Tenant shall reasonably agree upon if such rate ceases to be published) plus four (4) percentage points, and (ii) the highest rate permitted by applicable law.

26. LANDLORD’S RIGHT TO CURE DEFAULT; PAYMENTS BY TENANT.

26.1 Landlord’s Cure. All covenants and agreements to be kept or performed by Tenant under this Lease shall be performed by Tenant at Tenant’s sole cost and expense and without any reduction of Rent, except to the extent, if any, otherwise expressly provided herein. If Tenant shall fail to perform any obligation under this Lease, and such failure shall continue in excess of the time allowed under Section 19.1.2, above, unless a specific time period is otherwise stated in this Lease, Landlord may, but shall not be obligated to, make any such payment or perform any such act on Tenant’s part without waiving its rights based upon any default of Tenant and without releasing Tenant from any obligations hereunder.

26.1.1 Tenant’s Reimbursement. Except as may be specifically provided to the contrary in this Lease, Tenant shall pay to Landlord, upon delivery by Landlord to Tenant of statements therefor: (i) sums equal to expenditures reasonably made and obligations incurred by Landlord in connection with the remedying by Landlord of Tenant’s defaults pursuant to the provisions of Section 26.1; (ii) sums equal to all losses, costs, liabilities, damages and expenses referred to in Article 10 of this Lease; and (iii) subject to Section 29.21, sums equal to all expenditures made and obligations incurred by Landlord in collecting or attempting to collect the Rent or in enforcing or attempting to enforce any rights of Landlord under this Lease or pursuant to law, including, without limitation, all reasonable legal fees and other amounts so expended. Tenant’s obligations under this Section 26.2 shall survive the expiration or sooner termination of the Lease Term.

27. ENTRY BY LANDLORD. Landlord reserves the right at all reasonable times and upon reasonable notice to Tenant (except in the case of an Emergency) to enter the Premises to (i) inspect them; (ii) show the Premises to prospective purchasers, or to current or prospective mortgagees, ground or underlying lessors or insurers or, during the last nine (9) months of the Lease Term, to prospective tenants; (iii) post notices of nonresponsibility (to the extent applicable pursuant to then applicable law); or (iv) repair the Premises or the Building, or for structural repairs to the Building or the Building’s systems and equipment as provided under the Lease. Landlord may make any such entries without the abatement of Rent, except as otherwise provided in this Lease, and may take such reasonable steps as required to accomplish the stated purposes. In an Emergency, Landlord shall have the right to use any means that Landlord may deem proper to open the doors in and to the Premises. Any entry into the Premises by Landlord in the manner hereinbefore described shall not be deemed to be a forcible or unlawful entry into, or a detainer of, the Premises, or an actual or constructive eviction of Tenant from any portion of the Premises. Landlord shall use commercially reasonable efforts to minimize any interference with Tenant’s use of or access to the Premises in connection with any such entry, and shall comply with Tenant’s reasonable security measures. Landlord shall hold confidential any information regarding Tenant’s business that it may learn as a result of such entry.

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28. TENANT PARKING. Tenant shall have the right, without the payment of any parking charge or fee (other than as a reimbursement of operating expenses to the extent allowed pursuant to the terms or Article 4 of this Lease, above), commencing on the Lease Commencement Date, to use the amount of parking set forth in Section 9 of the Summary, in the on-site parking lot and garage which serves the Building. Tenant shall abide by all reasonable rules and regulations which are prescribed from time to time for the orderly operation and use of the parking facility where the parking passes are located (including any sticker or other identification system established by Landlord and the prohibition of vehicle repair and maintenance activities in the parking facilities), and shall cooperate in seeing that Tenant’s employees and visitors also comply with such rules and regulations. Tenant’s use of the Project parking facility shall be at Tenant’s sole risk and Tenant acknowledges and agrees that Landlord shall have no liability whatsoever for damage to the vehicles of Tenant, its employees and/or visitors, or for other personal injury or property damage or theft relating to or connected with the parking rights granted herein or any of Tenant’s, its employees’ and/or visitors’ use of the parking facilities.

29. MISCELLANEOUS PROVISIONS.

29.1 Terms; Captions. The words “Landlord” and “Tenant” as used herein shall include the plural as well as the singular. The necessary grammatical changes required to make the provisions hereof apply either to corporations or partnerships or individuals, men or women, as the case may require, shall in all cases be assumed as though in each case fully expressed. The captions of Articles and Sections are for convenience only and shall not be deemed to limit, construe, affect or alter the meaning of such Articles and Sections.

29.2 Binding Effect. Subject to all other provisions of this Lease, each of the covenants, conditions and provisions of this Lease shall extend to and shall, as the case may require, bind or inure to the benefit not only of Landlord and of Tenant, but also of their respective heirs, personal representatives, successors or assigns, provided this clause shall not permit any assignment by Tenant contrary to the provisions of Article 14 of this Lease.

29.3 No Air Rights. No rights to any view or to light or air over any property, whether belonging to Landlord or any other person, are granted to Tenant by this Lease. If at any time any windows of the Premises are temporarily darkened or the light or view therefrom is obstructed by reason of any repairs, improvements, maintenance or cleaning in or about the Project, the same shall be without liability to Landlord and without any reduction or diminution of Tenant’s obligations under this Lease.

29.4 Modification of Lease. Should any current or prospective mortgagee or ground lessor for the Building or Project require a modification of this Lease, which modification will not cause an increased cost or expense to Tenant or in any other way materially and adversely change the rights and obligations of Tenant hereunder or interfere with Tenant’s use of the Premises, then and in such event, Tenant agrees that this Lease may be so modified and agrees to execute whatever documents are reasonably required therefor and to deliver the same to Landlord within ten (10) business days following a request therefor. At the request of Landlord or any mortgagee or ground lessor, Tenant agrees to execute a short form of Lease and deliver the same to Landlord within ten (10) business days following the request therefor.

29.5 Transfer of Landlord’s Interest. Tenant acknowledges that Landlord has the right to transfer all or any portion of its interest in the Project or Building and in this Lease, and Tenant agrees that in the event of any such transfer, Landlord shall automatically be released from all liability under this Lease and Tenant agrees to look solely to such transferee for the performance of Landlord’s obligations hereunder accruing after the date of transfer provided such transferee shall have fully assumed and agreed in writing to be liable for all obligations of this Lease to be performed by Landlord, including the return of any security deposit or L-C, and Tenant shall attorn to such transferee.

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29.6 Prohibition Against Recording. Except as provided in Section 29.4 of this Lease, neither this Lease, nor any memorandum, affidavit or other writing with respect thereto, shall be recorded by Tenant or by anyone acting through, under or on behalf of Tenant.

29.7 Landlord’s Title. Landlord’s title is and always shall be paramount to the title of Tenant. Nothing herein contained shall empower Tenant to do any act which can, shall or may encumber the title of Landlord.

29.8 Relationship of Parties. Nothing contained in this Lease shall be deemed or construed by the parties hereto or by any third party to create the relationship of principal and agent, partnership, joint venturer or any association between Landlord and Tenant.

29.9 Payment under Protest. If Tenant in good faith disputes any amounts billed by Landlord, other than (i) Base Rent, (ii) Tenant’s Share of Direct Expenses (as to which Tenant may exercise its rights under Section 4.6, above), Tenant may make payment of such amounts under protest, and reserve all of its rights with respect to such amounts (the “Disputed Amounts”). Landlord and Tenant shall meet and confer to discuss the Disputed Amounts and attempt, in good faith, to resolve the particular dispute. If, despite such good faith efforts, Landlord and Tenant are unable to reach agreement regarding the Disputed Amounts, either party may submit the matter to binding arbitration under the JAMS Streamlined Arbitration Rules & Procedures. The non-prevailing party, as determined by JAMS, will be responsible to pay all fees and costs incurred in connection with the JAMS procedure, as well as all other costs and expenses, including reasonable attorneys’ fees, incurred by the prevailing party. This Section 29.9 shall not apply to claims relating to Landlord’s exercise of any unlawful detainer rights pursuant to California law or rights or remedies used by Landlord to gain possession of the Premises or terminate Lessee’s right of possession to the Premises.

29.10 Time of Essence. Time is of the essence with respect to the performance of every provision of this Lease in which time of performance is a factor.

29.11 Partial Invalidity. If any term, provision or condition contained in this Lease shall, to any extent, be invalid or unenforceable, the remainder of this Lease, or the application of such term, provision or condition to persons or circumstances other than those with respect to which it is invalid or unenforceable, shall not be affected thereby, and each and every other term, provision and condition of this Lease shall be valid and enforceable to the fullest extent possible permitted by law.

29.12 No Warranty. In executing and delivering this Lease, Tenant has not relied on any representations, including, but not limited to, any representation as to the amount of any item comprising Additional Rent or the amount of the Additional Rent in the aggregate or that Landlord is furnishing the same services to other tenants, at all, on the same level or on the same basis, or any warranty or any statement of Landlord which is not set forth herein or in one or more of the exhibits attached hereto.

29.13 Landlord Exculpation. The liability of Landlord or the Landlord Parties to Tenant for any default by Landlord under this Lease or arising in connection herewith or with Landlord’s operation, management, leasing, repair, renovation, alteration or any other matter relating to the Project or the Premises shall be limited solely and exclusively to an amount which is equal to the lesser of (a) the interest of Landlord in the Project or (b) the equity interest Landlord would have in the Project if the Project were encumbered by third-party debt in an amount equal to eighty percent (80%) of the value of the Project (as such value is determined by Landlord), including any rental, condemnation, sales and

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insurance proceeds received by Landlord or the Landlord Parties in connection with the Project, Building or Premises. No Landlord Parties (other than Landlord) shall have any personal liability therefor, and Tenant hereby expressly waives and releases such liability on behalf of itself and all persons claiming by, through or under Tenant. The limitations of liability contained in this Section 29.13 shall inure to the benefit of Landlord’s and the Landlord Parties’ present and future partners, beneficiaries, officers, directors, trustees, shareholders, agents and employees, and their respective partners, heirs, successors and assigns. Under no circumstances shall any present or future partner of Landlord (if Landlord is a partnership), or trustee or beneficiary (if Landlord or any partner of Landlord is a trust), have any liability for the performance of Landlord’s obligations under this Lease. Notwithstanding any contrary provision herein, neither Landlord nor the Landlord Parties shall be liable under any circumstances for injury or damage to, or interference with, Tenant’s business, including but not limited to, loss of profits, loss of rents or other revenues, loss of business opportunity, loss of goodwill or loss of use, in each case, however occurring, or loss to inventory, scientific research, scientific experiments, laboratory animals, products, specimens, samples, and/or scientific, business, accounting and other records of every kind and description kept at the premises and any and all income derived or derivable therefrom.

29.14 Entire Agreement. It is understood and acknowledged that there are no oral agreements between the parties hereto affecting this Lease and this Lease constitutes the parties’ entire agreement with respect to the leasing of the Premises and supersedes and cancels any and all previous negotiations, arrangements, brochures, agreements and understandings, if any, between the parties hereto or displayed by Landlord to Tenant with respect to the subject matter thereof, and none thereof shall be used to interpret or construe this Lease. None of the terms, covenants, conditions or provisions of this Lease can be modified, deleted or added to except in writing signed by the parties hereto.

29.15 Right to Lease. Landlord reserves the absolute right to effect such other tenancies in the Project as Landlord in the exercise of its sole business judgment shall determine to best promote the interests of the Building or Project. Tenant does not rely on the fact, nor does Landlord represent, that any specific tenant or type or number of tenants shall, during the Lease Term, occupy any space in the Building or Project.

29.16 Force Majeure. Any prevention, delay or stoppage due to strikes, lockouts, labor disputes, acts of God, acts of war, terrorist acts, inability to obtain services, labor, or materials or reasonable substitutes therefor, governmental actions, civil commotions, fire or other casualty, and other causes beyond the reasonable control of the party obligated to perform, except with respect to the obligations imposed with regard to Rent and other charges to be paid by Tenant pursuant to this Lease (collectively, a “Force Majeure”), notwithstanding anything to the contrary contained in this Lease, shall excuse the performance of such party for a period equal to any such prevention, delay or stoppage and, therefore, if this Lease specifies a time period for performance of an obligation of either party, that time period shall be extended by the period of any delay in such party’s performance caused by a Force Majeure, provided, however, the foregoing delays shall not apply to Tenant’s termination rights hereunder.

29.17 Intentionally Omitted.

29.18 Notices. All notices, demands, statements, designations, approvals or other communications (collectively, “Notices”) given or required to be given by either party to the other hereunder or by law shall be in writing, shall be (A) sent by United States certified or registered mail, postage prepaid, return receipt requested (“Mail”), (B) delivered by a nationally recognized overnight courier, or (C) delivered personally. Any Notice shall be sent, transmitted, or delivered, as the case may be, to Tenant at the appropriate address set forth in Section 10 of the Summary, or to such other place as Tenant may from time to time designate in a Notice to Landlord, or to Landlord at the addresses set forth

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below, or to such other places as Landlord may from time to time designate in a Notice to Tenant. Any Notice will be deemed given (i) three (3) business days after the date it is posted if sent by Mail, (ii) the date the overnight courier delivery is made, or (iii) the date personal delivery is made. As of the date of this Lease, any Notices to Landlord must be sent, transmitted, or delivered, as the case may be, to the following addresses:

HCP, Inc.

1920 Main Street, Suite 1200

Irvine, CA 92614

Attention: Legal Department

with a copy to

HCP Life Science Estates

950 Tower Lane, Suite 1650

Foster City, CA 94404

Attention: Jonathan M. Bergschneider

and

Allen Matkins Leck Gamble Mallory & Natsis LLP

1901 Avenue of the Stars, Suite 1800

Los Angeles, California 90067

Attention: Anton N. Natsis, Esq.

29.19 Joint and Several. If there is more than one tenant, the obligations imposed upon Tenant under this Lease shall be joint and several.

29.20 Authority. If Tenant is a corporation, trust or partnership, Tenant hereby represents and warrants that Tenant is a duly formed and existing entity qualified to do business in the State of California and that Tenant has full right and authority to execute and deliver this Lease and that each person signing on behalf of Tenant is authorized to do so.

29.21 Attorneys’ Fees. In the event that either Landlord or Tenant should bring suit for the possession of the Premises, for the recovery of any sum due under this Lease, or because of the breach of any provision of this Lease or for any other relief against the other, then all costs and expenses, including reasonable attorneys’ fees, incurred by the prevailing party therein shall be paid to the prevailing party by the other party, which obligation on the part of the other party shall be deemed to have accrued on the date of the commencement of such action and shall be enforceable whether or not the action is prosecuted to judgment.

29.22 Governing Law; WAIVER OF TRIAL BY JURY. This Lease shall be construed and enforced in accordance with the laws of the State of California. IN ANY ACTION OR PROCEEDING ARISING HEREFROM, LANDLORD AND TENANT HEREBY CONSENT TO (I) THE JURISDICTION OF ANY COMPETENT COURT WITHIN THE STATE OF CALIFORNIA, (II) SERVICE OF PROCESS BY ANY MEANS AUTHORIZED BY CALIFORNIA LAW, AND (III) IN THE INTEREST OF SAVING TIME AND EXPENSE, TRIAL WITHOUT A JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM BROUGHT BY EITHER OF THE PARTIES HERETO AGAINST THE OTHER OR THEIR SUCCESSORS IN RESPECT OF ANY MATTER ARISING OUT OF OR IN CONNECTION WITH THIS LEASE, THE RELATIONSHIP OF LANDLORD AND TENANT, TENANT’S USE OR OCCUPANCY OF THE PREMISES, AND/OR

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ANY CLAIM FOR INJURY OR DAMAGE, OR ANY EMERGENCY OR STATUTORY REMEDY. IN THE EVENT LANDLORD COMMENCES ANY SUMMARY PROCEEDINGS OR ACTION FOR NONPAYMENT OF BASE RENT OR ADDITIONAL RENT, TENANT SHALL NOT INTERPOSE ANY COUNTERCLAIM OF ANY NATURE OR DESCRIPTION (UNLESS SUCH COUNTERCLAIM SHALL BE MANDATORY) IN ANY SUCH PROCEEDING OR ACTION, BUT SHALL BE RELEGATED TO AN INDEPENDENT ACTION AT LAW.

29.23 Submission of Lease. Submission of this instrument for examination or signature by Tenant does not constitute a reservation of, option for or option to lease, and it is not effective as a lease or otherwise until execution and delivery by both Landlord and Tenant.

29.24 Brokers. Landlord and Tenant hereby warrant to each other that they have had no dealings with any real estate broker or agent in connection with the negotiation of this Lease, excepting only the real estate brokers or agents specified in Section 12 of the Summary (the “Brokers”), and that they know of no other real estate broker or agent who is entitled to a commission in connection with this Lease. Each party agrees to indemnify and defend the other party against and hold the other party harmless from any and all claims, demands, losses, liabilities, lawsuits, judgments, costs and expenses (including without limitation reasonable attorneys’ fees) with respect to any leasing commission or equivalent compensation alleged to be owing on account of any dealings with any real estate broker or agent, other than the Brokers, occurring by, through, or under the indemnifying party. The terms of this Section 29.24 shall survive the expiration or earlier termination of the Lease Term.

29.25 Independent Covenants. This Lease shall be construed as though the covenants herein between Landlord and Tenant are independent and not dependent and Tenant hereby expressly waives the benefit of any statute to the contrary and agrees that if Landlord fails to perform its obligations set forth herein, Tenant shall not be entitled to make any repairs or perform any acts hereunder at Landlord’s expense or to any setoff of the Rent or other amounts owing hereunder against Landlord.

29.26 Project or Building Name, Address and Signage. Landlord shall have the right at any time to change the name and/or address of the Project or Building (and Landlord shall reimburse Tenant its actual, reasonable costs incurred as a result of such change, if any) and, subject to Section 23.1, to install, affix and maintain any and all signs on the exterior and on the interior of the Project or Building as Landlord may, in Landlord’s sole discretion, desire. Tenant shall not use the name of the Project or Building or use pictures or illustrations of the Project or Building in advertising or other publicity or for any purpose other than as the address of the business to be conducted by Tenant in the Premises, without the prior written consent of Landlord.

29.27 Counterparts. This Lease may be executed in counterparts with the same effect as if both parties hereto had executed the same document. Both counterparts shall be construed together and shall constitute a single lease.

29.28 Good Faith. Except (i) for matters for which there is a standard of consent or discretion specifically set forth in this Lease; (ii) matters which could have an adverse effect on the Building Structure or the Building Systems, or which could affect the exterior appearance of the Building, or (iii) matters covered by Article 4 (Additional Rent), or Article 19 (Defaults; Remedies) of this Lease (collectively, the “Excepted Matters”), any time the consent of Landlord or Tenant is required, such consent shall not be unreasonably withheld or delayed, and, except with regard to the Excepted Matters, whenever this Lease grants Landlord or Tenant the right to take action, exercise discretion, establish rules and regulations or make an allocation or other determination, Landlord and Tenant shall act reasonably and in good faith.

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29.29 Development of the Project.

29.29.1 Subdivision. Landlord reserves the right to subdivide all or a portion of the buildings and Common Areas, so long as the same does not interfere with Tenant’s use of or access to the Premises or Tenant’s parking rights. Tenant agrees to execute and deliver, upon demand by Landlord and in the form requested by Landlord, any additional documents needed to conform this Lease to the circumstances resulting from a subdivision and any all maps in connection therewith, so long as the same does not increase Tenant’s obligations or decrease Tenant’s rights under this Lease. Notwithstanding anything to the contrary set forth in this Lease, the separate ownership of any buildings and/or Common Areas by an entity other than Landlord shall not affect the calculation of Direct Expenses or Tenant’s payment of Tenant’s Share of Direct Expenses.

29.29.2 Construction of Property and Other Improvements. Tenant acknowledges that portions of the Project may be under construction following Tenant’s occupancy of the Premises, and that such construction may result in levels of noise, dust, obstruction of access, etc. which are in excess of that present in a fully constructed project. Tenant hereby waives any and all rent offsets or claims of constructive eviction which may arise in connection with such construction, so long as the same does not interfere with Tenant’s use of or access to the Premises or Tenant’s parking rights.

29.29.3 No Violation. Tenant hereby warrants and represents that neither its execution of nor performance under this Lease shall cause Tenant to be in violation of any agreement, instrument, contract, law, rule or regulation by which Tenant is bound, and Tenant shall protect, defend, indemnify and hold Landlord harmless against any claims, demands, losses, damages, liabilities, costs and expenses, including, without limitation, reasonable attorneys’ fees and costs, arising from Tenant’s breach of this warranty and representation.

29.29.4 Transportation Management. Tenant shall fully comply with all present or future programs intended to manage parking, transportation or traffic in and around the Project and/or the Building, and in connection therewith, Tenant shall take responsible action for the transportation planning and management of all employees located at the Premises by working directly with Landlord, any governmental transportation management organization or any other transportation-related committees or entities. Such programs may include, without limitation: (i) restrictions on the number of peak-hour vehicle trips generated by Tenant; (ii) increased vehicle occupancy; (iii) implementation of an in-house ridesharing program and an employee transportation coordinator; (iv) working with employees and any Project, Building or area-wide ridesharing program manager; (v) instituting employer-sponsored incentives (financial or in-kind) to encourage employees to rideshare; and (vi) utilizing flexible work shifts for employees.

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IN WITNESS WHEREOF, Landlord and Tenant have caused this Lease to be executed the day and date first above written.

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EXHIBIT A

OUTLINE OF PREMISES; PROJECT SITE PLAN

[Schematic]

EXHIBIT A

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EXHIBIT B

TENANT WORK LETTER

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

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

(b) Architect: Landlord shall engage DGA with respect to any Tenant Improvements which Landlord is to cause to be constructed pursuant to this Tenant Work Letter.

(c) Tenant Change Request: See definition in Paragraph 2(c)(ii) hereof.

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

(e) General Contractor: The general contractor reasonably selected by Landlord with respect to Landlord’s TI Work. Tenant shall have no right to direct or control such General Contractor.

(f) Landlord’s TI Work: Any Tenant Improvements which Landlord is to construct or install pursuant to this Tenant Work Letter or by mutual agreement of Landlord and Tenant from time to time.

(g) Project Manager: Project Management Advisors, Inc., or any other project manager designated by Landlord in its reasonable discretion from time to time to act in a supervisory, oversight, project management or other similar capacity on behalf of Landlord in connection with the design and/or construction of the Tenant Improvements.

(h) 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 Tenant Improvements or Landlord’s Work as constructed to conform to the Approved TI Plans or this Tenant Work Letter in all material respects and that do not materially interfere with Tenant’s use or occupancy of the Building and the Premises.

(i) Substantial Completion Certificate: See definition in Paragraph 3(a) hereof.

(j) Tenant Delay: Any of the following types of delay in the completion of construction of Landlord’s TI Work (but in each instance, only to the extent that any of the following has actually and proximately caused substantial completion of Landlord’s TI Work to be delayed):

(i) Any delay resulting from Tenant’s failure to furnish, in a timely manner, information reasonably requested by Landlord or by Landlord’s Project Manager in connection with the design or construction of Landlord’s TI Work, or from Tenant’s failure to approve in a timely manner any matters requiring approval by Tenant;

EXHIBIT B

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(ii) Any delay resulting from Tenant Change 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 Tenant Change Request; or

(iii) Any delay caused by Tenant (or Tenant’s contractors, agents or employees) materially interfering with the performance of Landlord’s TI Work, provided that Landlord shall have given Tenant prompt notice of such material interference and, before the first time a Tenant Delay is deemed to have occurred as a result of such delay, such interference has continued for more than twenty-four (24) hours after Tenant’s receipt of such notice.

(k) Tenant Improvements: The improvements to or within the Building shown on the Approved TI Plans from time to time and to be constructed by Landlord pursuant to the Lease and this Tenant Work Letter. The term “Tenant Improvements” does not include the improvements existing in the Building and Premises at the date of execution of the Lease.

(l) Unavoidable Delays: Delays due to acts of God, acts of public agencies, labor disputes, strikes, fires, freight embargoes, inability (despite the exercise of due diligence) to obtain supplies, materials, fuels or permits, or other causes or contingencies (excluding financial inability) beyond the reasonable control of Landlord or Tenant, as applicable. Landlord shall use commercially reasonable efforts to provide Tenant with prompt notice of any Unavoidable Delays.

(m) Capitalized terms not otherwise defined in this Tenant Work Letter shall have the definitions set forth in the Lease.

2. Plans 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 Tenant Improvements.

(a) Approved Plans and Working Drawings for Tenant Improvements. Tenant shall promptly and diligently work with the Architect to cause to be prepared and delivered to Landlord for approval (which approval shall not be unreasonably withheld, conditioned or delayed by Landlord) proposed schematic plans and outline specifications for the Tenant Improvements. Following mutual approval of such proposed schematic plans and outline specifications by Landlord and by Tenant (as so approved, the “Approved Schematic Plans”), Tenant shall then work with the Architect to cause to be prepared, promptly and diligently (assuming timely delivery by Landlord of any information and decisions required to be furnished or made by Landlord in order to permit preparation of final working drawings, all of which information and decisions Landlord will deliver promptly and with reasonable diligence), and delivered to Landlord for approval (which approval shall not be unreasonably withheld, conditioned or delayed by Landlord) final detailed working drawings and specifications for the Tenant Improvements, including (without limitation) any applicable life safety, mechanical, electrical and plumbing working drawings and final architectural drawings (collectively, “Final TI Working Drawings”), which Final TI Working Drawings shall substantially conform to the Approved Schematic Plans. Upon receipt from Tenant of proposed schematic plans and outline specifications, proposed Final TI Working Drawings, any other plans and specifications, or any revisions or resubmittals of any of the foregoing, as applicable, Landlord shall promptly and diligently (and in all events within 10 business days after receipt in the case of an initial submittal of schematic plans and outline specifications or proposed Final TI Working Drawings, and within 7 business days after receipt in the case of any other plans and specifications or any revisions or resubmittals of any of the foregoing) either approve such proposed schematic plans and outline specifications or proposed Final TI Working Drawings, as applicable, or set forth in writing with particularity any changes necessary to bring the aspects of such proposed schematic plans and outline specifications or proposed Final TI Working Drawings into a form which will be

EXHIBIT B

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reasonably acceptable to Landlord. Upon approval of the Final TI Working Drawings by Landlord and Tenant, the Final TI Working Drawings shall constitute the “Approved TI Plans,” superseding (to the extent of any inconsistencies) any inconsistent features of the previously existing Approved Schematic Plans. Tenant shall respond to any request for information or approval of plans or drawings from Landlord or Architect within five (5) business days. Tenant acknowledges that the Tenant Improvements will include the items set forth on Schedule 2 to this Exhibit B, in order to allow the Premises to achieve a LEED “Silver” certification level.

(b) 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 Tenant pursuant to this Tenant Work Letter, 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 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 Architect for such item or component and an electrical engineer, mechanical engineer, structural engineer and civil engineer, if applicable); (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) costs for builder’s risk insurance; and (viii) all other “hard” and “soft” costs incurred in the construction of such item or component in accordance with the Approved TI Plans (if applicable) and this Tenant Work Letter; provided that the Cost of Improvements shall not include any internal or third-party costs incurred by Landlord except as provided in Section 2(e).

(c) Construction of Landlord’s TI Work. Following completion of the Approved TI Plans, Landlord shall apply for and use reasonable efforts to obtain the necessary permits and approvals to allow construction of all Tenant Improvements. Upon receipt of such permits and approvals, Landlord shall, at Tenant’s expense (subject to Landlord’s payment of the Tenant Improvement Allowance), construct and complete the Tenant Improvements substantially in accordance with the Approved TI Plans, subject to Unavoidable Delays and Tenant Delays (if any). Such construction of the Tenant Improvements and Landlord’s Work shall be performed in a neat, good and workmanlike manner, free of defects, using new materials and equipment of good quality, and shall materially conform to all applicable laws, rules, regulations, codes, ordinances, requirements, covenants, conditions and restrictions applicable thereto in force at the time such work is completed. Landlord shall cause Hathaway Dinwiddie, Landmark Builders and any other potential general contractors to bid on general conditions and fee for construction of the Tenant Improvements and provide an estimate for the direct cost of the Tenant Improvements. All bids will be opened together with Landlord selecting the general contractor to construct the Tenant Improvements, subject to the reasonable approval of Tenant. Tenant shall also have the right to approve all subcontractors engaged by the General Contractor, which approval shall not be unreasonably withheld, conditioned or delayed. Landlord shall enter into a stipulated sum or guaranteed maximum price construction contract with the General Contractor in the amount of the construction costs approved by Landlord and Tenant.

(d) Changes.

(i) If Landlord determines at any time that changes in the Final TI Working Drawings or in any other aspect of the Approved TI Plans relating to any item of Landlord’s TI Work are required as a result of applicable law or governmental requirements, or are required at the insistence of

EXHIBIT B

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any other third party whose approval may be required with respect to the Tenant 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) at Tenant’s sole cost and expense, subject to Landlord’s payment of the Tenant Improvement Allowance, cause revised Final TI Working Drawings to be prepared by the Architect and submitted to Tenant, for Tenant’s approval, which shall not be unreasonably withheld. Failure of Tenant to deliver to Landlord written notice of disapproval and specification of such required changes on or before any deadline reasonably specified by Landlord (which shall not be less than three (3) business days after delivery thereof to Tenant) shall constitute and be deemed to be a Tenant Delay to the extent Landlord is delayed in completing Landlord’s TI Work.

(ii) If Tenant at any time desires any changes, alterations or additions to the Final TI Working Drawings, Tenant shall submit a detailed written request to Landlord specifying such changes, alterations or additions (a “Tenant Change Request”). Upon receipt of any such request, Landlord shall promptly notify Tenant of (A) whether the matters proposed in the Tenant Change Request are approved by Landlord (which approval shall not be unreasonably withheld, conditioned or delayed by Landlord), (B) Landlord’s estimate of the number of days of delay, if any, which shall be caused in the construction of the Tenant Improvements by such Tenant Change 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 design, permitting, project management and construction of the Tenant Improvements affected by such Tenant Change Request if such Tenant Change 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 Tenant Change Request). If Landlord approves the Tenant Change Request and Tenant notifies Landlord in writing, within three (3) business days after receipt of such notice from Landlord, of Tenant’s approval of the Tenant Change Request (including the estimated delays and cost increases, if any, described in Landlord’s notice), then Landlord shall cause such Tenant Change Request to be implemented and Tenant shall be responsible for all actual costs or cost increases resulting from or attributable to the implementation of the Tenant Change Request, and any delays resulting therefrom shall be deemed to be a Tenant Delay (subject to Landlord’s payment of the Tenant Improvement Allowance). If Tenant fails to notify Landlord in writing of Tenant’s approval of such Tenant Change Request within said three (3) business day period, then such Tenant Change Request shall be deemed to be withdrawn and shall be of no further effect.

(e) Project Management. Unless and until revoked by Landlord by written notice delivered to Tenant, Landlord hereby (i) delegates to Project Manager the authority to exercise all approval rights, supervisory rights and other rights or powers of Landlord under this Tenant Work Letter with respect to the design and construction of the Tenant Improvements, 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 Tenant Improvements, including monitoring Tenant’s compliance with its obligations under this Tenant Work Letter and under the Lease with respect to the design and construction of the 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. Fees and charges of Project Manager for such services shall be at Tenant’s sole expense, subject to Landlord’s payment of the Tenant Improvement Allowance. Such fees shall not exceed $3.58 per RSF of the Premises (i.e., $272,699.00); provided that in the event Tenant elects to utilize all or any portion of the Additional TI Allowance pursuant to the terms of Section 4(b) below, such fees to the Project Manager shall increase by an amount equal to the product of (A) 2.65% and (B) the amount of the Additional TI Allowance which Tenant elects to utilize.

EXHIBIT B

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3. Completion.

(a) When Landlord receives written certification from Architect that construction of the Tenant Improvements and Landlord’s Work has been completed in accordance with the Approved TI Plans and Section 3(e) below (except for Punch List Work), Landlord shall prepare and deliver to Tenant a certificate (or separate certificates for the Tenant Improvements and Landlord’s Work) signed by Landlord, Architect and General Contractor (the “Substantial Completion Certificate”) (i) certifying that the construction of the Tenant Improvements and Landlord’s Work has been substantially completed in a good and workmanlike manner in accordance with the Approved TI Plans and Section 3(e) below in all material respects, subject only to completion of Punch List Work, and specifying the date of that completion, and (ii) certifying that the Tenant Improvements and Landlord’s Work comply in all material respects with all laws, rules, regulations, codes, ordinances, requirements, covenants, conditions and restrictions applicable thereto at the time of such delivery. Upon receipt by Tenant of the Substantial Completion Certificate and tender of possession of the Premises by Landlord to Tenant, and receipt of any certificate of occupancy or its legal equivalent, or other required sign-offs from any applicable governmental authority, allowing the legal occupancy of the Premises, the Tenant Improvements will be deemed delivered to Tenant and “Ready for Occupancy” for all purposes of the Lease (subject to Landlord’s continuing obligations with respect to any Punch List Work, and to any other express obligations of Landlord under the Lease or this Tenant Work Letter with respect to such Tenant Improvements).

(b) Immediately prior to delivery of the Substantial Completion Certificate for the Tenant Improvements, Project Manager or other representatives of Landlord shall conduct one or more “walkthroughs” of the Building with Tenant and Tenant’s representatives, to identify any items of Punch List Work that may require correction and to prepare a joint punch list reflecting any such items, following which Landlord shall diligently complete the Punch List Work reflected in such joint punch list. The Punch List Work shall be attached to the Substantial Completion Certificate, and shall not include damage caused by Tenant or any of Tenant’s agents in connection with any work performed by Tenant in the Premises, or required as a result of Tenant’s move-in to the Premises. At any time within thirty (30) days after delivery of such Substantial Completion Certificate, Tenant shall be entitled to submit one or more lists to Landlord supplementing such joint punch list by specifying any additional items of Punch List Work to be performed on the applicable Tenant Improvements and Landlord’s Work, and upon receipt of such list(s), Landlord shall diligently complete such additional Punch List Work. Promptly after Landlord provides Tenant with the Substantial Completion Certificate and completes all applicable Punch List Work for the Building, Landlord shall cause the recordation of a Notice of Completion (as defined in the California Civil Code) with respect to the Tenant Improvements.

(c) All construction, product and equipment warranties and guaranties obtained by Landlord with respect to the Tenant Improvements and Landlord’s Work shall, to the extent reasonably obtainable, include a provision that such warranties and guaranties shall also run to the benefit of Tenant, and Landlord shall cooperate with Tenant in a commercially reasonable manner to assist in enforcing all such warranties and guaranties for the benefit of Tenant.

(d) Notwithstanding any other provisions of this Tenant Work Letter or of the Lease, if Landlord is delayed in substantially completing any of the Tenant Improvements as a result of any Tenant Delay, and if the Lease Commencement Date is being determined under clause (i) of Section 3.2 of the Lease Summary, then notwithstanding any other provision of the Lease to the contrary, then the Premises shall be deemed to have been Ready for Occupancy on the date the Premises would have been Ready for Occupancy absent such Tenant Delay.

EXHIBIT B

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(e) Notwithstanding any other provisions of this Tenant Work Letter or of the Lease, Landlord shall be responsible, at Landlord’s sole cost and expense, and without deduction from the Tenant Improvement Allowance, to construct and deliver the Base Building and “Warm Shell” components of the Premises (“Landlord’s Work”), which shall consist of the items set forth on Schedule 1 to this Exhibit B (the “Warm Shell Schedule”).

(f) Construction of Additional Base Building Items. To the extent that the Final TI Working Drawings contain any structural items, or items which would not reasonably be categorized as “normal tenant improvements” under applicable GAAP standards (the “Additional Base Building Items”), then such Additional Base Building Items shall not be constructed as a part of the Landlord’s TI Work or the Tenant Improvements, but instead will be constructed by Landlord as a part of the Landlord’s Work. The cost of construction of the Additional Base Building Items (the “Additional Base Building Costs”) shall be borne by Landlord. Before commencing construction thereof, Landlord shall obtain a reasonable, good faith bid for the Additional Base Building Items from the General Contractor, which bid shall take into account all reasonable factors, including, without limitation, reasonable contingencies in connection therewith, Landlord shall notify Tenant of the amount of such bid (the “Estimated Base Building Costs”), and the amount of the Tenant Improvement Allowance shall be reduced by the amount of the Estimated Base Building Costs. Landlord shall have the right to disapprove any aspect of the Final TI Working Drawing that would result in Additional Base Building Costs in excess of the then remaining Tenant Improvement Allowance, so that, while the Tenant Improvement Allowance may be reduced, under no circumstances would Tenant be required to pay for any Additional Base Building Items with its own funds.

4. Payment of Costs.

(a) Tenant Improvement Allowance. Subject to any restrictions, conditions or limitations expressly set forth in this Tenant Work Letter or in the Lease or as otherwise expressly provided by mutual written agreement of Landlord and Tenant, the cost of construction of the Tenant Improvements shall be paid or reimbursed by Landlord up to a maximum amount equal to $10,283,355.00 (the “Tenant Improvement Allowance”), which amount is being made available by Landlord to be applied towards the Cost of Improvements for the construction of the Tenant Improvements in the Premises. Tenant shall be responsible, at its sole cost and expense, for payment of the entire Cost of Improvements of the Tenant Improvements in excess of the Tenant Improvement Allowance, including (but not limited to) any costs or cost increases incurred as a result of delays (unless caused by Landlord), governmental requirements or unanticipated conditions (unless caused by Landlord), and for payment of any and all costs and expenses relating to any alterations, additions, improvements, furniture, furnishings, equipment, fixtures and personal property items which are not eligible for application of Tenant Improvement Allowance funds under the restrictions expressly set forth below in this paragraph, but Tenant shall be entitled to use or apply the entire Tenant Improvement Allowance toward the Cost of Improvements of the Tenant Improvements (subject to any applicable restrictions, conditions, limitations, reductions or charges set forth in the Lease or in this Tenant Work Letter) prior to being required to expend any of Tenant’s own funds for the Tenant Improvements. The funding of the Tenant Improvement Allowance shall be made on a monthly basis or at other convenient intervals mutually approved by Landlord and Tenant and in all other respects shall be based on such commercially reasonable disbursement conditions and procedures as Landlord, Project Manager and Landlord’s lender (if any) may reasonably prescribe. Notwithstanding the foregoing provisions, under no circumstances shall the Tenant Improvement Allowance or any portion thereof be used or useable by Tenant 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 or 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 Building upon expiration or termination of the Lease. Notwithstanding anything to

EXHIBIT B

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the contrary herein, the Tenant Improvements shall not include (and Landlord shall be solely responsible for and the Tenant Improvement Allowance shall not be used for) the following: (a) costs incurred due to the presence of any Hazardous Materials in the Premises, if any, but with respect to removal and remediation of any such Hazardous Materials, only to the extent such removal or remediation is required by Applicable Laws enforced as of the date of this Lease for improvements in the Premises generally (as opposed to the specific Tenant Improvements) and to the extent the same required in order to allow Tenant to obtain a certificate of occupancy or its legal equivalent, for the Premises for the Permitted Use assuming a normal and customary occupancy density; (b) costs to bring the Project into compliance with Applicable Laws to the extent required in order to allow Tenant to obtain a certificate of occupancy or its legal equivalent, for the Premises for the Permitted Use assuming a normal and customary office occupancy density; (c) construction costs in excess of the contract amount stated in the contract with the General Contractor, as approved by Tenant (not to be unreasonably withheld), except for increases set forth in change orders approved by Tenant; (d) wages, labor and overhead for overtime and premium time unless approved by Tenant (which approval shall not be unreasonably withheld, conditioned or delayed); (e) attorneys’ fees incurred in connection with negotiation of construction contracts, and attorneys’ fees, experts’ fees and other costs in connection with disputes with third parties; (f) interest and other costs of financing construction costs; (g) costs incurred as a consequence construction defects or default by a contractor; (h) costs as a consequence of casualties; and (i) penalties and late charges attributable to Landlord’s failure to pay construction costs.

(b) Additional TI Allowance. In addition to the Tenant Improvement Allowance, Tenant shall have the right, by written notice to Landlord given on or before December 31, 2017, to use up to $30.00 per RSF of the Premises (i.e., up to $2,285,190.00) (the “Additional TI Allowance”) towards the payment of the costs of the Tenant Improvement Allowance Items. In the event Tenant exercises its right to use all or any portion of the Additional TI Allowance, Tenant shall be required to pay Landlord, commencing on the date the Tenant Improvements are completed (the “Additional Payment Commencement Date”), the “Additional TI Allowance Payment,” as that term is defined below, in consideration of Landlord provision of the Additional TI Allowance. The “Additional TI Allowance Payment” shall be determined as the missing component of an annuity, which annuity shall have (i) the amount of the Additional TI Allowance utilized by Tenant as the present value amount, (ii) a number equal to the number of full calendar months then remaining in the Lease Term as the number of payments, (iii) a monthly interest factor equal to seventy-five one-hundredths percent (0.75%), which is equal to nine percent (9%) divided by twelve (12) months per year, and (iv) the Additional TI Allowance Payment as the missing component of the annuity. Following the calculation of the Additional TI Allowance Payment, Landlord and Tenant will enter into a lease amendment in the form of Exhibit G attached hereto, to confirm the amount thereof.

5. No Agency. Nothing contained in this Tenant Work Letter shall make or constitute Tenant as the agent of Landlord.

6. Tenant Access. Provided that Tenant and its agents do not interfere with Contactor’s work in the Building and the Premises (including by the use of non-union vendors without prior coordination with Landlord), Contractor and Landlord shall allow Tenant access to the Premises at least thirty (30) days prior to the Substantial Completion of the Landlord’s TI Work without payment of Rent for the purpose of Tenant installing equipment or fixtures (including Tenant’s data and telephone equipment) in the Premises and preparing the Premises for occupancy. Prior to Tenant’s entry into the Premises as permitted by the terms of this Section 6, Tenant shall submit a schedule to Landlord and Contractor, for their approval, which schedule shall detail the timing and purpose of Tenant’s entry. Tenant shall hold Landlord harmless from and indemnify, protect and defend Landlord against any loss or damage to the Building or Premises and against injury to any persons caused by Tenant’s actions pursuant to this Section 6.

EXHIBIT B

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7. Miscellaneous. All references in this Tenant Work Letter to a number of days shall be construed to refer to calendar days, unless otherwise specified herein. In all instances where Landlord’s or Tenant’s approval is required, if no written notice of disapproval is given within the applicable time period, at the end of that period Landlord or Tenant shall be deemed to have given approval (unless the provision requiring Landlord’s or 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 Landlord or Tenant (as applicable) in a timely manner, the procedure for preparation of that item and approval shall be repeated. Landlord hereby acknowledges that Tenant shall not be required to restore the initial Tenant Improvements constructed in the Premises pursuant to the terms of this Tenant Work Letter upon the termination of the Lease.

8. Time Deadlines. Tenant shall use commercially reasonable, good faith, efforts and all due diligence to cooperate with the Architect, General Contractor and Landlord to complete all phases of the construction drawings set forth in this Tenant Work Letter and the permitting process and to receive the permits as soon as possible after the execution of the. The applicable dates for approval of items, plans and drawings as described in this Tenant Work Letter are set forth and further elaborated upon in Schedule 3 to this Exhibit B attached hereto (the “Time Deadlines”), attached hereto. Tenant agrees to utilize commercially reasonable efforts to comply with the Time Deadlines.

9. Rooftop Space. Tenant hereby acknowledges that to the extent either (i) any portion of the Tenant Improvements, or (ii) any of Tenant’s equipment installed in the Premises, requires a portion of the roof to be utilized by Tenant, that Tenant shall only be permitted to utilize that certain portion of the roof designated as “Zone 2” and “Zone 3” on Schedule 4 to this Exhibit B (the “Rooftop Space”).

10. Standard Tenant Improvement Package Specifications. Tenant hereby acknowledges that the Tenant Improvements are subject to the specifications set forth on Schedule 5 to this Exhibit B.

EXHIBIT B

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SCHEDULE 1 TO EXHIBIT B

BASE BUILDING “WARM SHELL” DELIVERY CONDITION

The Cove at Oyster Point

Building 3

151 Oyster Point Boulevard

South San Francisco, CA 94080

Warm-Shell Landlord Delivery Condition

SCHEDULE 1 TO EXHIBIT B

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SCHEDULE 1 TO EXHIBIT B

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SCHEDULE 1 TO EXHIBIT B

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SCHEDULE 1 TO EXHIBIT B

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SCHEDULE 1 TO EXHIBIT B

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SCHEDULE 1 TO EXHIBIT B

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SCHEDULE 2 TO EXHIBIT B

LEED REQUIREMENTS

The following is a list of LEED prerequisites and credits that all tenants are required to meet compliance for their associated tenant-occupied spaces beyond the current Core & Shell project scope. By signing this lease, tenants are agreeing to comply with all of the outlined requirements.

SCHEDULE 2 TO EXHIBIT B

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SCHEDULE 2 TO EXHIBIT B

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SCHEDULE 3 TO EXHIBIT B

TIME DEADLINES

THE COVE AT OYSTER POINT

South San Francisco, CA

151 Oyster Point, Third and Fourth Floors — CytomX TI

11/9/2015

Tenant Improvement Milestone Schedule

SCHEDULE 3 TO

EXHIBIT B

SCHEDULE 4 TO EXHIBIT B

ROOFTOP SPACE

[Schematic]

SCHEDULE 4 TO

EXHIBIT B

SCHEDULE 5 TO EXHIBIT B

[STANDARD TENANT IMPROVEMENT PACKAGE SPECIFICATIONS]

SCHEDULE 5 TO

EXHIBIT B

EXHIBIT C

NOTICE OF LEASE TERM DATES

Gentlemen:

In accordance with the Lease (the “Lease”), we wish to advise you and/or confirm as follows:

EXHIBIT C

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Agreed to and Accepted as

of _{____________}, 20__.

EXHIBIT C

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EXHIBIT D

FORM OF TENANT’S ESTOPPEL CERTIFICATE

The undersigned as Tenant under that certain Lease (the “Lease”) made and entered into as of                 , 20     by and between                              as Landlord, and the undersigned as Tenant, for Premises consisting of a portion of the building located at                                         , California, certifies as follows:

1. Attached hereto as Exhibit A is a true and correct copy of the Lease and all amendments and modifications thereto. The documents contained in Exhibit A represent the entire agreement between the parties as to the Premises.

2. The undersigned currently occupies the Premises described in the Lease, the Lease Term commenced on                     , and the Lease Term expires on                     , and the undersigned has no option to terminate or cancel the Lease or to purchase all or any part of the Premises, the Building and/or the Project, except as expressly set forth in the Lease.

3. Base Rent became payable on                 .

4. The Lease is in full force and effect and has not been modified, supplemented or amended in any way except as provided in Exhibit A.

5. Tenant has not transferred, assigned, or sublet any portion of the Premises nor entered into any license or concession agreements with respect thereto except as follows:

6. Tenant shall not modify the documents contained in Exhibit A without the prior written consent of Landlord’s mortgagee.

7. All monthly installments of Base Rent, all Additional Rent and all monthly installments of estimated Additional Rent have been paid when due through                 . The current monthly installment of Base Rent is

8. To Tenant’s actual knowledge, without inquiry, all conditions of the Lease to be performed by Landlord necessary to the enforceability of the Lease have been satisfied and Landlord is not in default thereunder. In addition, the undersigned has not delivered any notice to Landlord regarding a default by Landlord thereunder. The Lease does not require Landlord to provide any rental concessions or to pay any leasing brokerage commissions except as expressly set forth therein.

9. No rental has been paid more than thirty (30) days in advance and no security has been deposited with Landlord except as provided in the Lease. Neither Landlord, nor its successors or assigns, shall in any event be liable or responsible for, or with respect to, the retention, application and/or return to Tenant of any security deposit paid to any prior landlord of the Premises, whether or not still held by any such prior landlord, unless and until the party from whom the security deposit is being sought, whether it be a lender, or any of its successors or assigns, has actually received for its own account, as landlord, the full amount of such security deposit.

EXHIBIT D

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10. To Tenant’s actual knowledge, without inquiry, as of the date hereof, there are no existing defenses or offsets, or, to the undersigned’s knowledge, claims or any basis for a claim, that the undersigned has against Landlord.

11. If Tenant is a corporation or partnership, Tenant hereby represents and warrants that Tenant is a duly formed and existing entity qualified to do business in California and that Tenant has full right and authority to execute and deliver this Estoppel Certificate and that each person signing on behalf of Tenant is authorized to do so.

12. There are no actions pending against the undersigned under the bankruptcy or similar laws of the United States or any state.

13. Tenant is in full compliance with all federal, state and local laws, ordinances, rules and regulations affecting its use of the Premises, including, but not limited to, those laws, ordinances, rules or regulations relating to hazardous or toxic materials. Tenant has never permitted its agents, employees or contractors to engage in the generation, manufacture, treatment, use, storage, disposal or discharge of any hazardous, toxic or dangerous waste, substance or material in, on, under or about the Project or the Premises or any adjacent premises or property in violation of any federal, state or local law, ordinance, rule or regulation.

14. To the undersigned’s knowledge, all tenant improvement work to be performed by Landlord under the Lease has been completed in accordance with the Lease and has been accepted by the undersigned and all reimbursements and allowances due to the undersigned under the Lease in connection with any tenant improvement work have been paid in full. All work (if any) in the common areas required by the Lease to be completed by Landlord has been completed and all parking spaces required by the Lease have been furnished and/or all parking ratios required by the Lease have been met.

The undersigned acknowledges that this Estoppel Certificate may be delivered to Landlord or to a prospective mortgagee or prospective purchaser, and acknowledges that said prospective mortgagee or prospective purchaser will be relying upon the statements contained herein in making the loan or acquiring the property of which the Premises are a part and that receipt by it of this certificate is a condition of making such loan or acquiring such property.

Executed at                                  on the                      day of                         , 20    .

EXHIBIT D

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EXHIBIT E

ENVIRONMENTAL QUESTIONNAIRE

[ENVIRONMENTAL QUESTIONNAIRE

FOR COMMERCIAL AND INDUSTRIAL PROPERTIES]

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EXHIBIT G

FORM OF AGREEMENT FOR ADDITIONAL MONTHLY BASE RENT

FIRST AMENDMENT TO LEASE

This FIRST AMENDMENT TO LEASE (“Amendment”) is made and entered into as of                 , 2015, by and between HCP OYSTER POINT III LLC, a Delaware limited partner (“Landlord”), and CYTOMX THERAPEUTICS, INC., a Delaware limited liability company (“Tenant”).

R E C I T A L S :

A. Landlord and Tenant are parties to that certain Lease dated October         , 2015, (the “Lease”), pursuant to which Tenant leases the third and fourth floors (the “Premises”) containing approximately 76,173 rentable square feet of space in the building located at 151 Oyster Point Boulevard, South San Francisco, California (the “Building”).

B. Landlord and Tenant desire to amend the Lease on the terms and conditions set forth in this Amendment.

A G R E E M E N T :

NOW, THEREFORE, in consideration of the foregoing recitals and the mutual covenants contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows:

1. Terms. All capitalized terms when used herein shall have the same respective meanings as are given such terms in the Lease unless expressly provided otherwise in this Amendment.

2. Additional TI Allowance. Pursuant to the terms of Section 4 of the Tenant Work Letter attached to the Lease as Exhibit B, Tenant was entitled to an Additional TI Allowance of up to $2,285,190.00 (the “Additional TI Allowance”). Notwithstanding any provision to the contrary contained in the Lease, Landlord and Tenant hereby acknowledge and agree that Tenant has utilized                              and         /100 Dollars ($                ) of the Additional TI Allowance (the “Utilized Additional TI Allowance”).

4. Additional Monthly Base Rent. As a result of Tenant’s use of the Utilized Additional TI Allowance, Tenant is required to pay Additional Monthly Base Rent calculated as provided in Section 4 of the Tenant Work Letter, which Additional Monthly Base Rent shall be equal to $                     per month, payable on or before the first (1^st) day of each month commencing as of                 , and continuing through the expiration of the initial Lease Term.

5. No Further Modification. Except as specifically set forth in this Amendment, all of the terms and provisions of the Lease shall remain unmodified and in full force and effect.

EXHIBIT G

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IN WITNESS WHEREOF, this Amendment has been executed as of the day and year first above written.

EXHIBIT G

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EXHIBIT H

FORM OF LETTER OF CREDIT

(Letterhead of a money center bank

acceptable to the Landlord)

WE HEREBY ESTABLISH OUR IRREVOCABLE STANDBY LETTER OF CREDIT NO.                      IN YOUR FAVOR FOR THE ACCOUNT OF [Insert Tenant’s Name], A [Insert Entity Type], UP TO THE AGGREGATE AMOUNT OF USD[Insert Dollar Amount] ([Insert Dollar Amount] U.S. DOLLARS) EFFECTIVE IMMEDIATELY AND EXPIRING ON     Expiration Date) AVAILABLE BY PAYMENT UPON PRESENTATION OF YOUR DRAFT AT SIGHT DRAWN ON [Insert Bank Name] WHEN ACCOMPANIED BY THE FOLLOWING DOCUMENT(S):

1. THE ORIGINAL OF THIS IRREVOCABLE STANDBY LETTER OF CREDIT AND AMENDMENT(S), IF ANY.

2. BENEFICIARY’S SIGNED STATEMENT PURPORTEDLY SIGNED BY AN AUTHORIZED REPRESENTATIVE OF [Insert Landlord’s Name], A [Insert Entity Type] (“LANDLORD”) STATING THE FOLLOWING:

“THE UNDERSIGNED HEREBY CERTIFIES THAT THE LANDLORD, EITHER (A) UNDER THE LEASE (DEFINED BELOW), OR (B) AS A RESULT OF THE TERMINATION OF SUCH LEASE, HAS THE RIGHT TO DRAW DOWN THE AMOUNT OF USD                     IN ACCORDANCE WITH THE TERMS OF THAT CERTAIN OFFICE LEASE DATED [Insert Lease Date], AS AMENDED (COLLECTIVELY, THE “LEASE”), OR SUCH AMOUNT CONSTITUTES DAMAGES OWING BY THE TENANT TO BENEFICIARY RESULTING FROM THE BREACH OF SUCH LEASE BY THE TENANT THEREUNDER, OR THE TERMINATION OF SUCH LEASE, AND SUCH AMOUNT REMAINS UNPAID AT THE TIME OF THIS DRAWING.”

OR

EXHIBIT H

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“THE UNDERSIGNED HEREBY CERTIFIES THAT WE HAVE RECEIVED A WRITTEN NOTICE OF [Insert Bank Name]‘S ELECTION NOT TO EXTEND ITS STANDBY LETTER OF CREDIT NO.                      AND HAVE NOT RECEIVED A REPLACEMENT LETTER OF CREDIT WITHIN AT LEAST THIRTY (30) DAYS PRIOR TO THE PRESENT EXPIRATION DATE.”

OR

“THE UNDERSIGNED HEREBY CERTIFIES THAT BENEFICIARY IS ENTITLED TO DRAW DOWN THE FULL AMOUNT OF LETTER OF CREDIT NO.                          AS THE RESULT OF THE FILING OF A VOLUNTARY PETITION UNDER THE U.S. BANKRUPTCY CODE OR A STATE BANKRUPTCY CODE BY THE TENANT UNDER THAT CERTAIN OFFICE LEASE DATED [Insert Lease Date], AS AMENDED (COLLECTIVELY, THE “LEASE”), WHICH FILING HAS NOT BEEN DISMISSED AT THE TIME OF THIS DRAWING.”

OR

“THE UNDERSIGNED HEREBY CERTIFIES THAT BENEFICIARY IS ENTITLED TO DRAW DOWN THE FULL AMOUNT OF LETTER OF CREDIT NO.                          AS THE RESULT OF AN INVOLUNTARY PETITION HAVING BEEN FILED UNDER THE U.S. BANKRUPTCY CODE OR A STATE BANKRUPTCY CODE AGAINST THE TENANT UNDER THAT CERTAIN OFFICE LEASE DATED [Insert Lease Date], AS AMENDED (COLLECTIVELY, THE “LEASE”), WHICH FILING HAS NOT BEEN DISMISSED AT THE TIME OF THIS DRAWING.”

OR

“THE UNDERSIGNED HEREBY CERTIFIES THAT BENEFICIARY IS ENTITLED TO DRAW DOWN THE FULL AMOUNT OF LETTER OF CREDIT NO.                          AS THE RESULT OF THE REJECTION, OR DEEMED REJECTION, OF THAT CERTAIN OFFICE LEASE DATED [Insert Lease Date], AS AMENDED, UNDER SECTION 365 OF THE U.S. BANKRUPTCY CODE.”

SPECIAL CONDITIONS:

PARTIAL DRAWINGS AND MULTIPLE PRESENTATIONS MAY BE MADE UNDER THIS STANDBY LETTER OF CREDIT, PROVIDED, HOWEVER, THAT EACH SUCH DEMAND THAT IS PAID BY US SHALL REDUCE THE AMOUNT AVAILABLE UNDER THIS STANDBY LETTER OF CREDIT.

ALL INFORMATION REQUIRED WHETHER INDICATED BY BLANKS, BRACKETS OR OTHERWISE, MUST BE COMPLETED AT THE TIME OF DRAWING. [Please Provide The Required Forms For Review, And Attach As Schedules To The Letter Of Credit.]

ALL SIGNATURES MUST BE MANUALLY EXECUTED IN ORIGINALS.

ALL BANKING CHARGES ARE FOR THE APPLICANT’S ACCOUNT.

IT IS A CONDITION OF THIS STANDBY LETTER OF CREDIT THAT IT SHALL BE DEEMED AUTOMATICALLY EXTENDED WITHOUT AMENDMENT FOR A PERIOD OF ONE YEAR FROM THE PRESENT OR ANY FUTURE EXPIRATION DATE, UNLESS AT LEAST SIXTY (60) DAYS PRIOR TO THE EXPIRATION DATE WE SEND YOU NOTICE BY NATIONALLY

EXHIBIT H

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RECOGNIZED OVERNIGHT COURIER SERVICE THAT WE ELECT NOT TO EXTEND THIS LETTER OF CREDIT FOR ANY SUCH ADDITIONAL PERIOD. SAID NOTICE WILL BE SENT TO THE ADDRESS INDICATED ABOVE, UNLESS A CHANGE OF ADDRESS IS OTHERWISE NOTIFIED BY YOU TO US IN WRITING BY RECEIPTED MAIL OR COURIER. ANY NOTICE TO US WILL BE DEEMED EFFECTIVE ONLY UPON ACTUAL RECEIPT BY US AT OUR DESIGNATED OFFICE. IN NO EVENT, AND WITHOUT FURTHER NOTICE FROM OURSELVES, SHALL THE EXPIRATION DATE BE EXTENDED BEYOND A FINAL EXPIRATION DATE OF          (120 days from the Lease Expiration Date).

THIS LETTER OF CREDIT MAY BE TRANSFERRED SUCCESSIVELY IN WHOLE OR IN PART ONLY UP TO THE THEN AVAILABLE AMOUNT IN FAVOR OF A NOMINATED TRANSFEREE (“TRANSFEREE”), ASSUMING SUCH TRANSFER TO SUCH TRANSFEREE IS IN COMPLIANCE WITH ALL APPLICABLE U.S. LAWS AND REGULATIONS. AT THE TIME OF TRANSFER, THE ORIGINAL LETTER OF CREDIT AND ORIGINAL AMENDMENT(S) IF ANY, MUST BE SURRENDERED TO US TOGETHER WITH OUR TRANSFER FORM (AVAILABLE UPON REQUEST) AND PAYMENT OF OUR CUSTOMARY TRANSFER FEES, WHICH FEES SHALL BE PAYABLE BY APPLICANT (PROVIDED THAT BENEFICIARY MAY, BUT SHALL NOT BE OBLIGATED TO, PAY SUCH FEES TO US ON BEHALF OF APPLICANT, AND SEEK REIMBURSEMENT THEREOF FROM APPLICANT). IN CASE OF ANY TRANSFER UNDER THIS LETTER OF CREDIT, THE DRAFT AND ANY REQUIRED STATEMENT MUST BE EXECUTED BY THE TRANSFEREE AND WHERE THE BENEFICIARY’S NAME APPEARS WITHIN THIS STANDBY LETTER OF CREDIT, THE TRANSFEREE’S NAME IS AUTOMATICALLY SUBSTITUTED THEREFOR.

ALL DRAFTS REQUIRED UNDER THIS STANDBY LETTER OF CREDIT MUST BE MARKED: “DRAWN UNDER [Insert Bank Name] STANDBY LETTER OF CREDIT NO.                         .”

WE HEREBY AGREE WITH YOU THAT IF DRAFTS ARE PRESENTED TO [Insert Bank Name] UNDER THIS LETTER OF CREDIT AT OR PRIOR TO [Insert Time – (e.g., 11:00 AM)], ON A BUSINESS DAY, AND PROVIDED THAT SUCH DRAFTS PRESENTED CONFORM TO THE TERMS AND CONDITIONS OF THIS LETTER OF CREDIT, PAYMENT SHALL BE INITIATED BY US IN IMMEDIATELY AVAILABLE FUNDS BY OUR CLOSE OF BUSINESS ON THE SUCCEEDING BUSINESS DAY. IF DRAFTS ARE PRESENTED TO [Insert Bank Name] UNDER THIS LETTER OF CREDIT AFTER [Insert Time – (e.g., 11:00 AM)], ON A BUSINESS DAY, AND PROVIDED THAT SUCH DRAFTS CONFORM WITH THE TERMS AND CONDITIONS OF THIS LETTER OF CREDIT, PAYMENT SHALL BE INITIATED BY US IN IMMEDIATELY AVAILABLE FUNDS BY OUR CLOSE OF BUSINESS ON THE SECOND SUCCEEDING BUSINESS DAY. AS USED IN THIS LETTER OF CREDIT, “BUSINESS DAY” SHALL MEAN ANY DAY OTHER THAN A SATURDAY, SUNDAY OR A DAY ON WHICH BANKING INSTITUTIONS IN THE STATE OF CALIFORNIA ARE AUTHORIZED OR REQUIRED BY LAW TO CLOSE. IF THE EXPIRATION DATE FOR THIS LETTER OF CREDIT SHALL EVER FALL ON A DAY WHICH IS NOT A BUSINESS DAY THEN SUCH EXPIRATION DATE SHALL AUTOMATICALLY BE EXTENDED TO THE DATE WHICH IS THE NEXT BUSINESS DAY.

PRESENTATION OF A DRAWING UNDER THIS LETTER OF CREDIT MAY BE MADE ON OR PRIOR TO THE THEN CURRENT EXPIRATION DATE HEREOF BY HAND DELIVERY, COURIER SERVICE, OVERNIGHT MAIL, OR FACSIMILE. PRESENTATION BY FACSIMILE TRANSMISSION SHALL BE BY TRANSMISSION OF THE ABOVE REQUIRED SIGHT DRAFT DRAWN ON US TOGETHER WITH THIS LETTER OF CREDIT TO OUR FACSIMILE NUMBER, [Insert Fax Number – (        )             -                ], ATTENTION: [Insert Appropriate Recipient], WITH TELEPHONIC CONFIRMATION OF OUR RECEIPT OF SUCH FACSIMILE TRANSMISSION AT

EXHIBIT H

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OUR TELEPHONE NUMBER [Insert Telephone Number – (        )             -                ] OR TO SUCH OTHER FACSIMILE OR TELEPHONE NUMBERS, AS TO WHICH YOU HAVE RECEIVED WRITTEN NOTICE FROM US AS BEING THE APPLICABLE SUCH NUMBER. WE AGREE TO NOTIFY YOU IN WRITING, BY NATIONALLY RECOGNIZED OVERNIGHT COURIER SERVICE, OF ANY CHANGE IN SUCH DIRECTION. ANY FACSIMILE PRESENTATION PURSUANT TO THIS PARAGRAPH SHALL ALSO STATE THEREON THAT THE ORIGINAL OF SUCH SIGHT DRAFT AND LETTER OF CREDIT ARE BEING REMITTED, FOR DELIVERY ON THE NEXT BUSINESS DAY, TO [Insert Bank Name] AT THE APPLICABLE ADDRESS FOR PRESENTMENT PURSUANT TO THE PARAGRAPH FOLLOWING THIS ONE.

WE HEREBY ENGAGE WITH YOU THAT ALL DOCUMENT(S) DRAWN UNDER AND IN COMPLIANCE WITH THE TERMS OF THIS STANDBY LETTER OF CREDIT WILL BE DULY HONORED IF DRAWN AND PRESENTED FOR PAYMENT AT OUR OFFICE LOCATED AT [Insert Bank Name], [Insert Bank Address], ATTN: [Insert Appropriate Recipient], ON OR BEFORE THE EXPIRATION DATE OF THIS CREDIT,     (Expiration Date).

IN THE EVENT THAT THE ORIGINAL OF THIS STANDBY LETTER OF CREDIT IS LOST, STOLEN, MUTILATED, OR OTHERWISE DESTROYED, WE HEREBY AGREE TO ISSUE A DUPLICATE ORIGINAL HEREOF UPON RECEIPT OF A WRITTEN REQUEST FROM YOU AND A CERTIFICATION BY YOU (PURPORTEDLY SIGNED BY YOUR AUTHORIZED REPRESENTATIVE) OF THE LOSS, THEFT, MUTILATION, OR OTHER DESTRUCTION OF THE ORIGINAL HEREOF.

EXCEPT SO FAR AS OTHERWISE EXPRESSLY STATED HEREIN, THIS STANDBY LETTER OF CREDIT IS SUBJECT TO THE “INTERNATIONAL STANDBY PRACTICES” (ISP 98) INTERNATIONAL CHAMBER OF COMMERCE (PUBLICATION NO. 590).

EXHIBIT H

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CONSENT TO SUBLEASE AGREEMENT

THIS CONSENT TO SUBLEASE AGREEMENT (this “Agreement”) is made as of July 11, 2016, by and among HCP OYSTER POINT III LLC, a Delaware limited liability company (“Landlord”), CYTOMX THERAPEUTICS, INC., a Delaware corporation (“Tenant”), and ALECTOR LLC, a Delaware limited liability company (“Subtenant”).

RECITALS

A. Reference is hereby made to that certain Lease dated December 10, 2015, between Landlord and Tenant (the “Lease”), for certain premises comprised of approximately 76,173 rentable square feet of space (the “Premises”), located on the third and fourth floors of a four-story building at 151 Oyster Point Boulevard, South San Francisco, California 94080.

B. Pursuant to the terms of Article 14 of the Lease, Tenant has requested Landlord’s consent to that certain Sublease dated April 25, 2016, between Tenant and Subtenant (the “Sublease”), with respect to a subletting by Subtenant of a portion of the Premises comprised of approximately 15,748 rentable square feet of space, as more particularly described in the Sublease (the “Sublet Premises”). A copy of the Sublease is attached hereto as Exhibit A. Landlord is willing to consent to the Sublease in the terms and conditions contained herein.

C. All defined terms not otherwise expressly defined herein shall have the respective meanings given in the Lease.

AGREEMENT

1. Landlord’s Consent. Landlord hereby consents to the Sublease; provided, however, notwithstanding anything contained in the Sublease to the contrary, such consent is granted by Landlord only upon the terms and conditions set forth in this Agreement. The Sublease is subject and subordinate to the Lease. Landlord shall not be bound by any of the terms, covenants, conditions, provisions or agreements of the Sublease. Subtenant acknowledges for the benefit of Landlord that the Sublet Premises are presently being improved pursuant to Section 1.1.1 and Exhibit B of the Lease and that Landlord has made no representation or warranty to Subtenant as to the compliance of the Sublet Premises with any law, statute, ordinance, rule or regulation. Tenant and Subtenant hereby represent and warrant to Landlord that the copy of the Sublease attached hereto is a full, complete and accurate copy of the Sublease, and that there are no other documents or instruments relating to the use of the Sublet Premises by Subtenant other than the Sublease.

2. Reimbursement of Landlord. Within thirty (30) days after written request by Landlord, Tenant shall reimburse Landlord all of Landlord’s reasonable review and processing fees, as well as any reasonable professional fees, including, without limitation, all reasonable attorneys’ accountants’, architects’, engineers’ and consultants’ fees, incurred by Landlord in connection with its review and consent of the Sublease and preparation and negotiation of this Agreement, not to exceed $3,500.00.

3. Non-Release of Tenant; Further Transfers. Neither the Sublease nor this consent thereto shall release or discharge Tenant from any liability, whether past, present or future, under the Lease or alter the primary liability of the Tenant to pay the rent and perform and comply with all of the obligations of Tenant to be performed under the Lease (including the payment of all bills rendered by Landlord for charges incurred by the Subtenant for services and materials supplied to the Sublet Premises). Neither the Sublease nor this consent thereto shall be construed as a waiver of Landlord’s right to consent to any

further subletting either by Tenant or by the Subtenant, or to any assignment by Tenant of the Lease or assignment by the Subtenant of the Sublease, or as a consent to any portion of the Sublet Premises being used or occupied by any other party, except that Subtenant shall have the right to make a Permitted Transfer (as that term is defined in the Lease) without Landlord’s consent in accordance with Section 14.8 of the Lease. Landlord may consent to subsequent sublettings and assignments of the Lease or the Sublease or any amendments or modifications thereto without notifying Tenant nor anyone else liable under the Lease and without obtaining their consent. No such action by Landlord shall relieve such persons from any liability to Landlord or otherwise with regard to the Sublet Premises.

4. Relationship With Landlord. Tenant hereby assigns and transfers to Landlord the Tenant’s interest in the Sublease and all rentals and income arising therefrom, subject to the terms of this Section 4. Landlord, by consenting to the Sublease agrees that except while a default beyond applicable notice and cure periods shall exist in the performance of Tenant’s obligations under the Lease, Tenant may receive, collect and enjoy the rents accruing under the Sublease. In the event Tenant shall default beyond applicable notice and cure periods in the performance of its obligations to Landlord under the Lease (whether or not Landlord terminates the Lease), Landlord may at its option by notice to Tenant, either (i) terminate the Sublease (only if Landlord terminates the Lease), (ii) elect to receive and collect, directly from Subtenant, all rent and any other sums owing and to be owed under the Sublease, as further set forth in Section 4.1, below, or (iii) elect to succeed to Tenant’s interest in the Sublease and cause Subtenant to attorn to Landlord, as further set forth in Section 4.2, below (only if Landlord terminates the Lease).

4.1 Landlord’s Election to Receive Rents. Landlord shall not, by reason of the Sublease, nor by reason of the collection of rents or any other sums from the Subtenant pursuant to Section 4, item (ii), above, be deemed liable to Subtenant for any failure of Tenant to perform and comply with any obligation of Tenant, and Tenant hereby irrevocably authorizes and directs Subtenant, upon receipt of any written notice from Landlord stating that a default beyond applicable notice and cure periods exists in the performance of Tenant’s obligations under the Lease, to pay to Landlord the rents and any other sums due and to become due under the Sublease. Tenant agrees that Subtenant shall have the right to rely upon any such statement and request from Landlord, and that Subtenant shall pay any such rents and any other sums to Landlord without any obligation or right to inquire as to whether such default exists and notwithstanding any notice from or claim from Tenant to the contrary. Tenant shall not have any right or claim against Subtenant for any such rents or any other sums so paid by Subtenant to Landlord. Landlord shall credit Tenant with any rent received by Landlord under such assignment but the acceptance of any payment on account of rent from the Subtenant as the result of any such default shall in no manner whatsoever be deemed an attornment by the Landlord to Subtenant or by Subtenant to Landlord, be deemed a waiver by Landlord of any provision of the Lease, or serve to release Tenant from any liability under the terms, covenants, conditions, provisions or agreements under the Lease. Notwithstanding the foregoing, any other payment of rent from the Subtenant directly to Landlord, regardless of the circumstances or reasons therefor, shall in no manner whatsoever be deemed an attornment by the Subtenant to Landlord in the absence of a specific written agreement signed by Landlord to such an effect.

4.2 Landlord’s Election of Tenant’s Attornment. In the event Landlord elects, at its option, to cause Subtenant to attorn to Landlord pursuant to Section 4, item (iii), above, Landlord shall undertake the obligations of Tenant under the Sublease from the time of the exercise of the option, but Landlord shall not (i) be liable for any prepayment of more than one month’s rent or any security deposit paid by Subtenant (unless actually received by Landlord), (ii) be liable for any previous act or omission of Tenant under the Lease or for any other defaults of Tenant under the Sublease, (iii) be subject to any defenses or offsets previously accrued which Subtenant may have against Tenant, or (iv) be bound by any changes or modifications made to the Sublease without the written consent of Landlord.

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4.3 Operational Matters. Notwithstanding Landlord’s consent to the Sublease as set forth herein, Landlord shall not be obligated to accept from Subtenant any payments of Base Rent or Additional Rent due under the Lease, all of which shall be paid by Tenant as set forth in the Lease. Requests for building services as provided under the Lease, including without limitation, parking privileges, repair and maintenance services, or any other services or obligations to be performed by Landlord under the terms of the Lease, shall be made by Tenant, and Landlord shall have no obligation to respond to any direct request of Subtenant regarding the same.

4.4 No Waiver. The acceptance of any amounts by Landlord from Subtenant or any other party shall not be deemed a waiver by Landlord of the obligation of Tenant to pay any or all amount due and owing under the Lease. The performance of any obligation required by Tenant under the Lease by Subtenant or any other party shall not be deemed a waiver by Landlord of the duty of Tenant to perform such obligation or any other obligation as to which performance is or becomes due under the Lease.

4.5 Acts of Subtenant. Any act or omission by Subtenant, or by any other person or entity for whose acts or omissions Tenant is liable or responsible under the terms of the Lease, that violates any of the provisions of the Lease, shall be deemed a violation of the Lease by Tenant, subject to any applicable notice and cure provisions contained in the Lease.

4.6 Indemnification. Except as provided in Section 10.5 of the Lease or to the extent due to the negligence, willful misconduct or violation of the Lease by Landlord or the Landlord Parties, Subtenant hereby assumes all risk of damage to property or injury to persons in, upon or about the Premises from any cause whatsoever (including, but not limited to, any personal injuries resulting from a slip and fall in, upon or about the Premises) and agrees that Landlord, its partners, subpartners and their respective officers, agents, servants, employees, and independent contractors shall not be liable for, and are hereby released from any responsibility for, any damage either to person or property or resulting from the loss of use thereof, which damage is sustained by Subtenant or by other persons claiming through Subtenant. Tenant shall indemnify, defend, protect, and hold Landlord harmless from any and all loss, cost, damage, expense and liability (including without limitation court costs and reasonable attorneys’ fees) incurred in connection with or arising from any cause in, on or about the Premises (including, but not limited to, a slip and fall), any acts, omissions or negligence of Subtenant or of any person claiming by, through or under Subtenant, or of the contractors, agents, servants, employees, invitees, guests or licensees of Subtenant or any such person, in, on or about the Premises, provided that the terms of the foregoing indemnity shall not apply to the negligence or willful misconduct of Landlord or the Landlord Parties, or Landlord’s breach of its obligations under the Lease. The provisions of this Section 4.6 shall survive the expiration or sooner termination of the Sublease with respect to any claims or liability arising in connection with any event occurring prior to such expiration or termination.

4.7 Insurance. Prior to Subtenant’s occupancy of the Sublet Premises, Subtenant shall provide Landlord with certificates of all of the insurance required to be carried by Subtenant by the terms of the Lease and the Sublease, which shall show Landlord as being an additional insured thereunder. The waiver of subrogation contained in Section 10.5 of the Lease shall apply as between Landlord and Subtenant.

4.8 No Consent to Alterations or Particular Use. Notwithstanding anything contained in the Sublease to the contrary, Landlord’s consent to the Sublease as contained in this Agreement shall not be deemed to be a consent to (i) any alteration or work of improvement that Tenant or Subtenant may desire or intend in the Sublet Premises, except that Landlord hereby approves of the Sublessee Changes (as defined in the Sublease) pursuant to Paragraph 2.C of the Sublease and the restoration of such Sublessee Changes to the configuration shown on the Plans (as defined in the Sublease), (ii) any use of

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hazardous, radioactive or toxic materials in or about the Sublet Premises, except that Sublessee shall be permitted to use the Hazardous Materials identified on the Environmental Questionnaire attached as Exhibit D to the Sublease (as the same may be updated from time to time pursuant to Section 5.3 of the Lease), or (iii) any signage proposed to be installed for the benefit of Subtenant, except that Landlord agrees that, without reducing or diminishing Tenant’s right to install its name in such locations, Subtenant may have the rights described in Section 23.1(i)-(iii) of the Lease to install certain exterior signage (“Exterior Signage”), provided that such Exterior Signage shall be considered “Tenant Signage” under the Lease, such rights are within and not in addition to the existing rights provided to Tenant by Section 23.1(i)-(iii) of the Lease, and such Exterior Signage shall remain subject to Landlord’s approval rights (including with respect to the Sign Specifications defined in the Lease) in connection with Tenant Signage under Article 23 of the Lease.

5. General Provisions.

5.1 Consideration for Sublease. Tenant and Subtenant represent and warrant that there are no additional payments of rent or any other consideration of any type payable by Subtenant to Tenant with regard to the Sublet Premises other than as disclosed in the Sublease.

5.2 Brokerage Commission. Tenant and Subtenant covenant and agree that under no circumstances shall Landlord be liable for any brokerage commission or other charge or expense in connection with the Sublease and Tenant and Subtenant agree to protect, defend indemnify and hold Landlord harmless from and against the same and from any cost or expense (including, but not limited to, attorneys’ fees) incurred by Landlord in resisting any claim for any such brokerage commission.

5.3 Recapture. This consent shall in no manner be construed as limiting Landlord’s ability to exercise any rights to recapture any portion of the Premises, as set forth in the Lease, in the event of a proposed future sublease or assignment of such portion of the Premises.

5.4 Controlling Law. The terms and provisions of this Agreement shall be construed in accordance with and governed by the laws of the State of California.

5.5 Binding Effect. This Agreement shall be binding upon and inure to the benefit of the parties hereto, their heirs, successors and permitted assigns. As used herein, the singular number includes the plural and the masculine gender includes the feminine and neuter.

5.6 Captions. The paragraph captions utilized herein are in no way intended to interpret or limit the terms and conditions hereof; rather, they are intended for purposes of convenience only.

5.7 Partial Invalidity. If any term, provision or condition contained in this Agreement shall, to any extent, be invalid or unenforceable, the remainder of this Agreement, or the application of such term, provision or condition to persons or circumstances other than those with respect to which it is invalid or unenforceable, shall not be affected thereby, and each and every other term, provision and condition of this Agreement shall be valid and enforceable to the fullest extent permitted by law.

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5.8 Attorneys’ Fees. If either party commences litigation against the other for the specific performance of this Agreement, for damages for the breach hereof or otherwise for enforcement of any remedy hereunder, the parties hereto agree to and hereby do waive any right to a trial by jury and, in the event of any such commencement of litigation, the prevailing party shall be entitled to recover from the other party such costs and reasonable attorneys’ fees as may have been incurred.

[Signatures follow on next page]

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IN WITNESS WHEREOF, the parties have executed this Consent to Sublease Agreement as of the day and year first above written.

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