Ellie Mae, Inc. Common Stock, par value $0.0001 per share Underwriting Agreement

Exhibit 1.1

Ellie Mae, Inc.

Common Stock, par value $0.0001 per share

Underwriting Agreement

June 27, 2012

William Blair & Company, L.L.C.,

As representative of the several Underwriters

named in Schedule I hereto,

c/o William Blair & Company, L.L.C.

222 West Adams Street

Chicago, Illinois 60606

Ladies and Gentlemen:

Ellie Mae, Inc., a Delaware corporation (the “Company”), proposes, subject to the terms and conditions stated herein, to issue and sell to the Underwriters named in Schedule I hereto (the “Underwriters”) for whom William Blair & Company, L.L.C. is acting as representative (the “Representative” or “you”) an aggregate of 3,000,000 shares and, at the election of the Underwriters solely to cover over-allotments, if any, up to 465,245 additional shares of Common Stock, par value $0.0001 per share, (“Stock”) of the Company and the stockholders of the Company named in Schedule II hereto (the “Selling Stockholders”) propose, subject to the terms and conditions stated herein, to sell to the Underwriters an aggregate of 101,638 shares of Stock. The aggregate of 3,101,638 shares to be sold by the Company and the Selling Stockholders is herein called the “Firm Shares” and the aggregate of 465,245 additional shares to be sold by the Company solely to cover over-allotments, if any, is herein called the “Optional Shares.” The Firm Shares and the Optional Shares that the Underwriters elect to purchase pursuant to Section 2 hereof are herein collectively called the “Shares.”

1. (a) The Company (and, with respect to the representations contained in Sections 1(a)(B) through (E) only, the Selling Stockholders listed in Schedule IIa hereto (the “Management Selling Stockholders”)) represents and warrants to, and agrees with, each of the Underwriters that:

(A) A registration statement on Form S-3 (File No. 333-181980) (the “Initial Registration Statement”) in respect of the Shares has been filed with the Securities and Exchange Commission (the “Commission”); the Initial Registration Statement and any post-effective amendment thereto, each in the form heretofore delivered to you, and, excluding exhibits thereto but including all documents incorporated by reference in the prospectus contained therein, to you for each of the other Underwriters, have been declared effective by the Commission in such form; other than a registration statement, if any, increasing the size of the offering (a “Rule 462(b) Registration Statement”), filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Act”), which became effective upon filing, and any preliminary prospectus supplement to the base prospectus included in the Initial Registration Statement and filed with the Commission pursuant to Rule 424(b) under the Act, no other document with respect to the Initial Registration Statement or document incorporated by reference therein has heretofore been filed with the Commission; and no stop order suspending the effectiveness of the Initial Registration Statement, any post-effective amendment thereto or the Rule 462(b) Registration Statement, if any, has been issued and no proceeding for that purpose has been initiated or, to the knowledge of the Company, threatened by the Commission (any preliminary prospectus included in the Initial Registration Statement or filed with the Commission pursuant to Rule 424(b)under the Act, including the base prospectus included in the Initial Registration Statement as supplemented by any preliminary prospectus supplement thereto, is hereinafter called a “Preliminary Prospectus”; the various parts of the Initial Registration Statement and the Rule 462(b) Registration Statement, if any, including all exhibits thereto and including (i) the information contained in the form of final prospectus, including any prospectus supplement thereto, filed with the Commission pursuant to Rule 424(b) under the Act in accordance with Section 5(a) hereof, and deemed by virtue of Rule 430B or Rule 430C under the Act to be part of the Initial Registration Statement at the time it was declared effective and (ii) the documents incorporated by reference in the Preliminary Prospectus contained in the Initial Registration Statement at the time such part of the Initial Registration Statement became effective, each as amended at the time such part of the Initial Registration Statement became effective or such part of the Rule 462(b) Registration Statement, if any, became or hereafter becomes effective, are hereinafter collectively called the “Registration Statement”; the Preliminary Prospectus relating to the Shares that was included in the Registration Statement immediately prior to the Applicable Time (as defined in Section 1(a)(D) hereof) is hereinafter called the “Pricing Prospectus”; such final prospectus, including the base prospectus in the Registration Statement and any prospectus supplement thereto, in the form first filed pursuant to Rule 424(b) under the Act, is hereinafter called the “Prospectus”; any reference herein to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Act, as of the date of such Preliminary Prospectus or Prospectus, as the case may be; any reference to any amendment or supplement to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after the date of such Preliminary Prospectus or Prospectus, as the case may be, under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and incorporated by reference in such Preliminary Prospectus or Prospectus, as the case may be; any reference to any amendment to the Registration Statement shall be deemed to refer to and include any annual report of the Company filed pursuant to Section 13(a) or 15(d) of the Exchange Act after the effective date of the Initial Registration Statement that is incorporated by reference in the Registration Statement; and any “issuer free writing prospectus” as defined in Rule 405 under the Act prepared by or on behalf of the Company or used or referred to by the Company in connection with the offering of the Shares is hereinafter called an “Issuer Free Writing Prospectus”); and the Pricing Prospectus, together with the information included in Schedule III(a) hereto and each Issuer Free Writing Prospectus filed or used by the Company on or before the Applicable Time, other than a road show that is an Issuer Free Writing Prospectus but is not required to be filed pursuant to Rule 433 under the Act, is hereinafter called the “Pricing Disclosure Package”;

(B) No order preventing or suspending the use of any Preliminary Prospectus or any Issuer Free Writing Prospectus has been issued by the Commission, and each Preliminary Prospectus, at the time of filing thereof, conformed in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder, and did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that this representation and warranty shall not apply to (i) any statements or omissions made in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through William Blair & Company, L.L.C. expressly for use therein (the “Underwriter Information”) or (ii) the addresses of the Selling Stockholders that are not Management Selling Stockholders (the “Selling Stockholder Information”);

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(C) Each document incorporated by reference in the Pricing Disclosure Package and the Prospectus, when it became effective or was filed with the Commission, as the case may be, conformed in all material respects to the requirements of the Act or the Exchange Act, as applicable, and the rules and regulations of the Commission thereunder, and none of such documents contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading; and any further document so filed and incorporated by reference in the Prospectus or any further amendment or supplement thereto, when such document becomes effective or is filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Act or the Exchange Act, as applicable, and the rules and regulations of the Commission thereunder and will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; provided, however, that this representation and warranty shall not apply to any statements or omissions made in reliance upon and in conformity with the Underwriter Information;

(D) For the purposes of this Agreement, the “Applicable Time” is 6:30 p.m. (Eastern time) on the date of this Agreement. The Pricing Disclosure Package, as of the Applicable Time, did not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; and each Issuer Free Writing Prospectus listed on Schedule III(b) hereto does not conflict with the information contained in the Registration Statement, the Pricing Disclosure Package or the Prospectus and each such Issuer Free Writing Prospectus, as supplemented by and taken together with the Pricing Disclosure Package as of the Applicable Time, did not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that this representation and warranty shall not apply to statements or omissions made in the Pricing Disclosure Package in reliance upon and in conformity with the Underwriter Information;

(E) The Registration Statement, (a) at the time it initially became effective, (b) at the time of each amendment thereto for purposes of complying with Section 10(a)(3) of the Act (whether by post-effective amendment, incorporated report or form of prospectus), (c) at the time of the first contract of sale for the Shares, and (d) at the Time of Delivery (as defined in Section 4 below), conformed and will conform, and the Prospectus (a) on its date, (b) at the time of filing the Prospectus pursuant to Rule 424(b), and (c) at the Time of Delivery, and any further amendments or supplements to the Registration Statement or the Prospectus will conform, in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder and do not and will not, as of the applicable effective date as to each part of the Registration Statement and as of the applicable filing date as to the Prospectus and any amendment or supplement thereto, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; provided, however, that this representation and warranty shall not apply to any statements or omissions made in reliance upon and in conformity with the Underwriter Information;

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(F) Other than as set forth or described in the Pricing Disclosure Package, since the date of the latest audited financial statements included or incorporated by reference in the Pricing Prospectus, none of the Company or any of its subsidiaries has sustained any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree; and, since the respective dates as of which information is given in the Registration Statement and the Pricing Disclosure Package, (i) there has not been any change in the capital stock or long-term debt of the Company or any of its subsidiaries, taken as a whole (other than changes pursuant to agreements or employee benefit plans or in connection with the exercise of options or warrants, in each case as described or referred to in the Pricing Disclosure Package) or (ii) or any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries, taken as a whole (a “Material Adverse Effect”);

(G) Except as set forth, incorporated by reference or described in the Registration Statement, Pricing Disclosure Package and Prospectus, the Company and its subsidiaries do not own any real property and have good and marketable title to all personal property owned by them which is material to the business of the Company, in each case free and clear of all liens, encumbrances and defects except such as do not materially affect the value of such property and do not interfere with the use made and proposed to be made of such property by the Company and its subsidiaries; and any real property and buildings held under lease by the Company and its subsidiaries are held by them under valid, subsisting and enforceable leases with such exceptions as are not material and do not interfere with the use made and proposed to be made of such property and buildings by the Company and its subsidiaries;

(H) The Company (i) has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Delaware, with corporate power and corporate authority to own its properties and conduct its business as described in the Pricing Disclosure Package, and (ii) has been duly qualified as a foreign corporation for the transaction of business and is in good standing under the laws of each other jurisdiction in which it owns or leases properties or conducts any business so as to require such qualification, except in the case of clause (ii), where the failure to be so qualified or in good standing would not have a Material Adverse Effect; and each subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation;

(I) The Company has an authorized capitalization as set forth in the Pricing Prospectus in the column entitled “Actual” under the caption “Capitalization” (except for subsequent issuances, if any, pursuant to agreements or employee benefit plans or in connection with the exercise of options or warrants, in each case as described or referred to in the Pricing Disclosure Package); and all of the issued shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable and conform in all material respects to the description of the Stock contained in the Pricing Prospectus and Prospectus; and all of the issued shares of capital stock of each subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and (except for directors’ qualifying shares) are owned directly or indirectly by the Company, free and clear of all liens, encumbrances or claims;

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(J) The unissued Shares to be issued and sold by the Company to the Underwriters hereunder have been duly and validly authorized and, when issued and delivered against payment therefor as provided herein, will be duly and validly issued and fully paid and non-assessable and will conform in all material respects to the description of the Stock contained in the Prospectus;

(K) The issue and sale of the Shares and the compliance by the Company with this Agreement and the consummation of the transactions herein contemplated will not materially conflict with or result in a material breach or violation of any of the terms or provisions of, or constitute a material default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, will not result in any violation of the provisions of the Certificate of Incorporation or By-laws of the Company or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties, and no consent, approval, authorization, order, registration or qualification of or with any such court or governmental agency or body is required for the issue and sale of the Shares or the consummation by the Company of the transactions contemplated by this Agreement, except (i) the registration under the Act of the Shares, (ii) such consents, approvals, authorizations, registrations or qualifications as may be required under state securities or Blue Sky laws, and (iii) the approval of the Financial Industry Regulatory Agency, Inc. (“FINRA”) of the underwriting terms and arrangements in connection with the purchase and distribution of the Shares by the Underwriters;

(L) Neither the Company nor any of its subsidiaries is (i) in violation of its Certificate of Incorporation or By-laws or (ii) in default in the performance or observance of any obligation, agreement, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which it is a party or by which it or any of its properties may be bound, except in the case of clause (ii), for such defaults that would not have a Material Adverse Effect;

(M) The statements set forth in the Pricing Prospectus and the Prospectus (i) under the caption “Description of Our Capital Stock”, insofar as they purport to constitute a summary of the terms of the Stock, under the caption “Business—Government Regulation” and under the caption “Certain Relationships and Related Transactions”, insofar as they purport to describe the provisions of the laws and documents referred to therein, are accurate, complete and fair in all material respects and (ii) under the caption “Material United States Federal Income Tax Consequences to Non-U.S. Holders”, insofar as they constitute summaries of U.S. federal income tax law and regulations or legal conclusions with respect thereto, constitute accurate summaries of the matters described therein in all material respects;

(N) Other than as set forth in the Pricing Disclosure Package, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject which, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate reasonably be expected to have a Material Adverse Effect; and, to the Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others;

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(O) The Company is not and, after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Pricing Disclosure Package, will not be an “investment company”, as such term is defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”);

(P) At the time of filing the Initial Registration Statement the Company was not and is not an “ineligible issuer,” as defined under Rule 405 under the Act;

(Q) Grant Thornton LLP, which has certified certain financial statements of the Company and its subsidiaries, are independent public accountants as required by the Act and the rules and regulations of the Commission thereunder;

(R) The Company maintains a system of internal control over financial reporting (as such term is defined in Rule 13a-15(f) under the Exchange Act) that complies with the requirements of the Exchange Act and has been designed by the Company’s principal executive officer and principal financial officer, or under their supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles in the United States (“GAAP”). Except as disclosed in the Registration Statement, the Company’s internal control over financial reporting is effective and the Company is not aware of any material weaknesses in its internal control over financial reporting;

(S) Since the date of the latest audited financial statements included in the Pricing Prospectus, there has been no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting;

(T) The Company maintains disclosure controls and procedures (as such term is defined in Rule 13a-15(e) under the Exchange Act) that comply with the requirements of the Exchange Act; such disclosure controls and procedures have been designed to ensure that material information relating to the Company and its subsidiaries is made known to the Company’s principal executive officer and principal financial officer by others within those entities; and such disclosure controls and procedures are effective;

(U) The Company and its subsidiaries own or possess, or can acquire on reasonable terms, adequate rights to use all material patents, patent rights, licenses, inventions, copyrights, know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), trademarks, service marks, trade names or other intellectual property (collectively “Intellectual Property”) necessary to carry on the business now operated by them or as described in the Pricing Disclosure Package to be operated by them, and, other than as set forth in the Pricing Disclosure Package, neither the Company nor any of its subsidiaries has received any notice of or is otherwise aware of any infringement of, or conflict with, asserted rights of others with respect to any Intellectual Property or of any facts or circumstances which would render any Intellectual Property invalid or inadequate to protect the interest of the Company or any of its subsidiaries therein, and which infringement or conflict (if the subject of any unfavorable decision, ruling or finding) or invalidity or inadequacy that would, individually or in the aggregate, result in a Material Adverse Effect;

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(V) The financial statements, including the notes thereto, and the supporting schedules included or incorporated by reference in the Registration Statement, the Pricing Prospectus and the Prospectus present fairly in all material respects the financial position at the dates indicated and the cash flows and results of operations for the periods indicated of the Company and its consolidated subsidiaries; except as otherwise stated in the Registration Statement, the Pricing Prospectus and the Prospectus, such financial statements have been prepared in conformity with GAAP applied on a consistent basis throughout the periods involved; and the supporting schedules, if any, included or incorporated by reference in the Registration Statement, the Pricing Prospectus and the Prospectus present fairly the information required to be stated therein. The selected historical financial data set forth or incorporated by reference in the Registration Statement, Pricing Prospectus and Prospectus under the caption “Prospectus Summary—Summary Consolidated Financial Data” present fairly in all material respects the information included therein; management’s assumptions provide a reasonable basis for presenting the significant effects directly attributable to the transactions and events and the related pro forma adjustments set forth in the pro forma financial statements included or incorporated by reference in the Registration Statement, the Pricing Prospectus and the Prospectus give appropriate effect to those assumptions. No other financial statements or supporting schedules are required to be included in the Registration Statement. The other financial and related statistical information included or incorporated by reference in the Registration Statement, the Pricing Prospectus and the Prospectus presents fairly in all material respects the information included therein and has been prepared on a basis consistent with that of the financial statements that are included or incorporated by reference in the Registration Statement, the Pricing Prospectus and the Prospectus and the books and records of the respective entities presented therein;

(W) There are no off-balance sheet arrangements (as defined in Regulation S-K Item 303(a)(4)(ii)) that may have a material current or future effect on the Company’s financial condition, changes in financial condition, results of operations, liquidity, capital expenditures or capital resources;

(X) Since the date as of which information is given or incorporated by reference in the Pricing Prospectus, and except as may otherwise be disclosed in the Pricing Prospectus, the Company has not (i) issued or granted any securities, other than pursuant to employee benefit plans, stock option plans or other employee compensation plans disclosed in the Pricing Prospectus or pursuant to outstanding options, rights or warrants, (ii) incurred any material liability or obligation, direct or contingent, other than liabilities and obligations which were incurred in the ordinary course of business, (iii) entered into any material transaction not in the ordinary course of business or (iv) declared or paid any dividends on its capital stock;

(Y) The Company has not sold or issued any shares of Common Stock during the six-month period preceding the date of the Prospectus, including any sales pursuant to Regulation D of, the Act, other than (i) shares issued pursuant to employee benefit plans, stock option plans or other employee compensation plans or pursuant to outstanding options, rights or warrants, or (ii) as disclosed in the Pricing Disclosure Package;

(Z) There are no contracts or other documents which are required to be described in the Registration Statement, the Pricing Prospectus or the Prospectus or to be filed as an exhibit to the Registration Statement which have not been described or filed as required;

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(AA) Except as described in the Pricing Disclosure Package, there are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with this offering;

(BB) Except as described in the Pricing Disclosure Package, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in the securities registered pursuant to the Registration Statement or in any securities being registered pursuant to any other registration statement filed by the Company under the Act;

(CC) The holders of outstanding shares of the Company’s capital stock are not entitled to preemptive or other rights to subscribe for the Shares that have not been complied with or otherwise effectively waived;

(DD) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened;

(EE) Neither the Company nor any of its subsidiaries nor any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”); and the Company will not directly or indirectly use the proceeds of the offering of the Shares, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC;

(FF) The Company has not taken and will not take, directly or indirectly, any action which is designed to or which has constituted or which would reasonably be expected to cause or result in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Shares;

(GG) Each of the Company products has been at all times up to and including the sale thereof produced, maintained, sold or provided in compliance in all material respects with all privacy and data protection laws and regulations applicable to the Company’s collection, handling, and storage of its customers’ data. The Company has policies and procedures in place designed to ensure the integrity and security of the data collected, handled or stored in connection with the delivery of its product offerings. The Company complies with, and takes appropriate steps reasonably designed to assure compliance in all material respects with such policies and procedures;

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(HH) The statistical and market-related data included in the Pricing Disclosure Package are based on or derived from sources which the Company believes are reliable and accurate;

(II) No “nationally recognized statistical rating organization,” as that term is defined by the Commission in Section 3(a)(62) of the Exchange Act has issued a rating on the credit of the Company or any debt securities or preferred stock of the Company;

(JJ) The Company and each of its subsidiaries carry, or are covered by, insurance from insurers of recognized financial responsibility in such amounts and covering such risks as the Company and its subsidiaries reasonably believe is adequate for the conduct of their respective businesses and the value of their respective properties, except where the failure to carry or maintain such insurance would not, individually or in the aggregate, have a Material Adverse Effect;

(KK) The Company and its subsidiaries have filed all material foreign, federal, state and local tax returns required to be filed by them through the date hereof, or have duly requested extensions thereof, and have paid all taxes shown as due thereon, and all such tax returns are true and correct in all material respects. No deficiencies for taxes of the Company or its subsidiaries have been assessed by a tax authority, and no deficiencies for taxes of the Company or its subsidiaries have, to the Company’s knowledge, been proposed by a tax authority, except for such deficiencies as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect;

(LL) The Company and each of its subsidiaries have such permits, licenses, patents, franchises, certificates of need and other approvals or authorizations of governmental or regulatory authorities (“Permits”) as are necessary under applicable law to own their properties and conduct their businesses in the manner described in the Pricing Prospectus and the Prospectus, except for any of the foregoing that would not, in the aggregate, reasonably be expected to have a Material Adverse Effect; each of the Company and its subsidiaries has fulfilled and performed all of its obligations with respect to the Permits, and no event has occurred that allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other impairment of the rights of the holder or any such Permits, except for any of the foregoing that would not reasonably be expected to have a Material Adverse Effect; and

(MM) Except as described in the Pricing Prospectus and the Prospectus, no material relationship, direct or indirect, exists between or among the Company, on the one hand, and the directors, officers, shareholders, customers or suppliers of the Company, on the other hand, that is required to be disclosed in the Pricing Prospectus and the Prospectus pursuant to Section 404 of Regulation S-K.

(b) Each of the Selling Stockholders severally, and not jointly, as to itself represents and warrants to, and agrees with, each of the Underwriters and the Company that:

(A) Except for (i) such consents, approvals, authorizations, registrations or qualifications as may be required under state securities or Blue Sky laws in connection with the purchase and distribution of the Shares by the Underwriters, (ii) the approval by FINRA of the underwriting terms and arrangements in connection with the purchase and distribution of the Shares by the Underwriters, and (iii) such consents or approvals that have already been obtained, all consents, approvals, authorizations and orders necessary for the execution and delivery by such Selling Stockholder of this Agreement and the Power of Attorney and the Custody Agreement (each as defined below), and for the sale and delivery of the Shares to be sold by such Selling Stockholder hereunder, have been obtained; and such Selling Stockholder has full right, power and authority to enter into this Agreement, the Power-of-Attorney and the Custody Agreement and to sell, assign, transfer and deliver the Shares to be sold by such Selling Stockholder hereunder;

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(B) The sale of the Shares to be sold by such Selling Stockholder hereunder and the compliance by such Selling Stockholder with all of the provisions of this Agreement, the Power of Attorney and the Custody Agreement and the consummation of the transactions herein and therein contemplated will not materially conflict with or result in a material breach or violation of any of the terms or provisions of, or constitute a material default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which such Selling Stockholder is a party or by which such Selling Stockholder is bound or to which any of the property or assets of such Selling Stockholder is subject, or result in any violation of the provisions of the Certificate of Incorporation or By-laws (or similar governing documents) of such Selling Stockholder to the extent that such Selling Stockholder is a corporation or other entity or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over such Selling Stockholder or the property of such Selling Stockholder;

(C) Such Selling Stockholder has, with respect to Shares other than the unissued Shares to be issued upon exercise of options (the “Options”) to be exercised by certain of the Selling Stockholders in connection with the offering and sale of the Shares to the Underwriters, and immediately prior to the First Time of Delivery (as defined in Section 4 hereof) such Selling Stockholder will have, assuming due issuance of any Shares to be issued upon exercise of Options, good and valid title to, and if such Shares are uncertificated, a valid “security entitlement” within the meaning of Section 8-501 of the New York Uniform Commercial Code (the “UCC”) in respect of, the Shares to be sold by such Selling Stockholder hereunder, free and clear of all liens, encumbrances or claims, except for any liens, encumbrances or claims arising under the Custody Agreement or otherwise in favor of the Underwriters;

(D) Such Selling Stockholder has not taken and will not take, directly or indirectly, any action which is designed to or which has constituted or would reasonably be expected to cause or result in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Shares;

(E) To the extent that any statements or omissions made in the Registration Statement, any Preliminary Prospectus, the Prospectus, any amendment or supplement thereto or any Issuer Free Writing Prospectus are made in reliance upon and in conformity with written information furnished to the Company by such Selling Stockholder expressly for use therein, such Preliminary Prospectus, Issuer Free Writing Prospectus and the Registration Statement did, and the Prospectus and any further amendments or supplements to the Registration Statement and the Prospectus, when they become effective or are filed with the Commission, as the case may be, and each Issuer Free Writing Prospectus disseminated after the Applicable Time, will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading;

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(F) In order to document the Underwriters’ compliance with the reporting and withholding provisions of the Tax Equity and Fiscal Responsibility Act of 1982 with respect to the transactions herein contemplated, such Selling Stockholder has delivered or will deliver to you prior to or at the First Time of Delivery (as hereinafter defined) a properly completed and executed United States Treasury Department Form W-9 (or other applicable form or statement specified by Treasury Department regulations in lieu thereof);

(G) Certificates in negotiable form or shares in book-entry form representing all of the Shares to be sold by such Selling Stockholder hereunder, other than any such Shares to be issued upon the exercise of Options, and duly completed and executed irrevocable Option exercise notices with respect to all of such Shares to be issued upon the exercise of Options (if applicable) have been placed in custody under a Custody Agreement, in the form heretofore furnished to you (the “Custody Agreement”), duly executed and delivered by such Selling Stockholder to Wells Fargo Bank, N.A., as custodian (the “Custodian”), and such Selling Stockholder has duly executed and delivered a Power of Attorney, in the form heretofore furnished to you (the “Power of Attorney”), appointing the persons indicated in Schedule II hereto, and each of them, as such Selling Stockholder’s attorneys-in-fact (the “Attorneys-in-Fact”) with authority to execute and deliver this Agreement on behalf of such Selling Stockholder, to determine the purchase price to be paid by the Underwriters to the Selling Stockholders as provided in Section 2 hereof, to authorize the delivery of the Shares to be sold by such Selling Stockholder hereunder, to authorize (if applicable) the exercise of the Options to be exercised with respect to the Shares to be sold by such Selling Stockholder hereunder and otherwise to act on behalf of such Selling Stockholder in connection with the transactions contemplated by this Agreement and the Custody Agreement;

(H) The Shares represented by the certificates held in custody for such Selling Stockholder under the Custody Agreement are subject to the interests of the Underwriters hereunder; the arrangements made by such Selling Stockholder for such custody, and the appointment by such Selling Stockholder of the Attorneys-in-Fact by the Power of Attorney, are to that extent irrevocable; the obligations of the Selling Stockholders hereunder shall not be terminated by operation of law, whether by the death or incapacity of any individual Selling Stockholder or, in the case of an estate or trust, by the death or incapacity of any executor or trustee or the termination of such estate or trust, or in the case of a partnership or corporation, by the dissolution of such partnership or corporation, or by the occurrence of any other event; if any individual Selling Stockholder or any such executor or trustee should die or become incapacitated, or if any such estate or trust should be terminated, or if any such partnership or corporation should be dissolved, or if any other such event should occur, before the delivery of the Shares hereunder, certificates representing the Shares shall be delivered by or on behalf of the Selling Stockholders in accordance with the terms and conditions of this Agreement and of the Custody Agreements; and actions taken by the Attorneys-in-Fact pursuant to the Powers of Attorney shall be as valid as if such death, incapacity, termination, dissolution or other event had not occurred, regardless of whether or not the Custodian, the Attorneys-in-Fact, or any of them, shall have received notice of such death, incapacity, termination, dissolution or other event; and

(I) The sale of the Shares to be sold by the Selling Stockholders pursuant to this Agreement is not prompted by any information concerning the Company or any of its subsidiaries that is not set forth in the Registration Statement, the Pricing Prospectus, the Prospectus or any amendment or supplement thereto.

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2. Subject to the terms and conditions herein set forth, (a) the Company and each of the Selling Stockholders agree, severally and not jointly, to sell to each of the Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company and each of the Selling Stockholders, at a purchase price per share of $16.15, the number of Firm Shares (to be adjusted by you as necessary so as to eliminate fractional shares) determined by multiplying the aggregate number of Firm Shares to be sold by the Company and each of the Selling Stockholders as set forth opposite their respective names in Schedule II hereto by a fraction, the numerator of which is the aggregate number of Firm Shares to be purchased by such Underwriter as set forth opposite the name of such Underwriter in Schedule I hereto and the denominator of which is the aggregate number of Firm Shares to be purchased by all of the Underwriters from the Company and all of the Selling Stockholders hereunder and (b) in the event and to the extent that the Underwriters shall exercise the election to purchase Optional Shares as provided below, the Company agrees to sell to each of the Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company, at the purchase price per share set forth in clause (a) of this Section 2, that portion of the number of Optional Shares as to which such election shall have been exercised (to be adjusted by you so as to eliminate fractional shares) determined by multiplying such number of Optional Shares by a fraction, the numerator of which is the maximum number of Optional Shares which such Underwriter is entitled to purchase as set forth opposite the name of such Underwriter in Schedule I hereto and the denominator of which is the maximum number of Optional Shares that all of the Underwriters are entitled to purchase hereunder.

The Company hereby grants to the Underwriters the right to purchase at their election up to 465,245 Optional Shares, at the purchase price per share set forth in the paragraph above, for the sole purpose of covering sales of shares in excess of the number of Firm Shares, provided that the purchase price per Optional Share shall be reduced by an amount per share equal to any dividends or distributions declared by the Company and payable on the Firm Shares but not payable on the Optional Shares. Any such election to purchase Optional Shares may be exercised only for the purpose of covering overallotments and by written notice from you to the Company, given within a period of 30 calendar days after the date of this Agreement and setting forth the aggregate number of Optional Shares to be purchased and the date on which such Optional Shares are to be delivered, as determined by you but in no event earlier than the First Time of Delivery (as defined in Section 4 hereof) or, unless you and the Company otherwise agree in writing, earlier than two or later than ten business days after the date of such notice.

3. Upon the authorization by you of the release of the Firm Shares, the several Underwriters propose to offer the Firm Shares for sale upon the terms and conditions set forth in the Prospectus.

4. (a) The Shares to be purchased by each Underwriter hereunder, in uncertificated form, and in such authorized denominations and registered in such names as William Blair & Company, L.L.C. may request upon at least forty-eight hours’ prior notice to the Company and the Selling Stockholders shall be delivered by or on behalf of the Company and the Selling Stockholders to William Blair & Company, L.L.C., through the facilities of the Depository Trust Company (“DTC”) or its designated custodian (the “Designated Office”), for the account of such Underwriter, against payment by or on behalf of such Underwriter of the purchase price therefor by wire transfer of Federal (same-day) funds to the account specified by the Company and the Custodian to William Blair & Company, L.L.C. at least forty-eight hours in advance. The time and date of such delivery and payment shall be, with respect to the Firm Shares, 9:30 a.m., New York City time, on July 3, 2012 or such other time and date as William Blair & Company, L.L.C., the Company and the Selling Stockholders may agree upon in writing, and, with respect to the Optional Shares, 9:30 a.m., New York City time, on the date specified by William Blair & Company, L.L.C. in the written notice given by William Blair & Company, L.L.C. of the Underwriters’ election to purchase such Optional Shares, or such other time and date as William Blair & Company, L.L.C. and the Company may agree upon in writing. Such time and date for delivery of the Firm Shares is herein called the “First Time of Delivery”, such time and date for delivery of the Optional Shares, if not the First Time of Delivery, is herein called the “Second Time of Delivery”, and each such time and date for delivery is herein called a “Time of Delivery”.

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(b) The documents to be delivered at each Time of Delivery by or on behalf of the parties hereto pursuant to Section 8 hereof, including the cross receipt for the Shares and any additional documents requested by the Underwriters pursuant to Section 8(k) hereof, will be delivered at the offices of Latham & Watkins LLP, 140 Scott Drive, Menlo Park, California 94025 (the “Closing Location”), and the Shares will be delivered at the Designated Office, all at such Time of Delivery. A meeting will be held at the Closing Location at 2:00 p.m., Pacific Time, on the New York Business Day immediately preceding such Time of Delivery, at which meeting the final drafts of the documents to be delivered pursuant to the preceding sentence will be available for review by the parties hereto. For the purposes of this Section 4, “New York Business Day” shall mean each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in New York City are generally authorized or obligated by law or executive order to close.

5. The Company agrees with each of the Underwriters:

(a) To prepare the Prospectus in a form approved by you and to file such Prospectus pursuant to Rule 424(b) under the Act not later than the Commission’s close of business on the second business day following the execution and delivery of this Agreement; to make no further amendment or any supplement to the Registration Statement or the Prospectus prior to the last Time of Delivery which shall be reasonably disapproved by you promptly after reasonable notice thereof (other than an amendment or supplement which the Company believes, based on advice of legal counsel, it is required by law to file or use); to file in a timely manner all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Shares; to advise you, promptly after it receives notice thereof, of the time when any amendment to the Registration Statement has been filed or becomes effective or any amendment or supplement to the Prospectus has been filed and to furnish you with copies thereof if requested by you; to file promptly all material required to be filed by the Company with the Commission pursuant to Rule 433(d) under the Act; to advise you, promptly after it receives notice thereof, of the issuance by the Commission of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus or other prospectus in respect of the Shares, of the suspension of the qualification of the Shares for offering or sale in any jurisdiction, of the initiation or threatening of any proceeding for any such purpose, or of any request by the Commission for the amending or supplementing of the Registration Statement or the Prospectus or for additional information; and, in the event of the issuance of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus or other prospectus or suspending any such qualification, to promptly use its reasonable best efforts to obtain the withdrawal of such order;

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(b) Promptly from time to time to take such action as you may reasonably request to qualify the Shares for offering and sale under the securities laws of such jurisdictions as you may request and to comply with such laws so as to permit the continuance of sales and dealings therein in such jurisdictions for as long as may be necessary to complete the distribution of the Shares, provided that in connection therewith the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file a general consent to service of process in any jurisdiction or (iii) subject itself to taxation in any jurisdiction if it is not otherwise so subject;

(c) Prior to 10:00 a.m., New York City time, on the second New York Business Day next succeeding the date of this Agreement and from time to time, to furnish the Underwriters with written and electronic copies of the Prospectus in New York City in such quantities as you may reasonably request, and, if the delivery of a prospectus (or in lieu thereof, the notice referred to in Rule 173(a) under the Act) is required at any time prior to the expiration of nine months after the time of issue of the Prospectus in connection with the offering or sale of the Shares and if at such time any event shall have occurred as a result of which the Prospectus as then amended or supplemented would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made when such Prospectus (or in lieu thereof, the notice referred to in Rule 173(a) under the Act) is delivered, not misleading, or, if for any other reason it shall be necessary during such period to amend or supplement the Prospectus or to file under the Exchange Act any document incorporated by reference in the Prospectus in order to comply with the Act or the Exchange Act, to notify you and upon your request to file such document and to prepare and furnish without charge to each Underwriter and to any dealer in securities as many written and electronic copies as you may from time to time reasonably request of an amended Prospectus or a supplement to the Prospectus which will correct such statement or omission or effect such compliance, and in case any Underwriter is required to deliver a prospectus (or in lieu thereof, the notice referred to in Rule 173(a) under the Act) in connection with sales of any of the Shares at any time nine months or more after the time of issue of the Prospectus, upon your request but at the expense of such Underwriter, to prepare and deliver to such Underwriter as many written and electronic copies as you may request of an amended or supplemented Prospectus complying with Section 10(a)(3) of the Act;

(d) To make generally available to its securityholders (which may be satisfied by filing with the Commission’s Electronic, Gathering, Analysis and Retrieval System (“EDGAR”)) as soon as practicable, but in any event not later than sixteen months after the effective date of the Registration Statement (as defined in Rule 158(c) under the Act), an earnings statement of the Company and its subsidiaries (which need not be audited) complying with Section 11(a) of the Act and the rules and regulations of the Commission thereunder (including, at the option of the Company, Rule 158);

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(e) During the period beginning from the date hereof and continuing to and including the date 90 days after the date of the Prospectus (the “Lock-Up Period”), not to offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of, except as provided hereunder, any securities of the Company that are substantially similar to the Shares, including but not limited to any options or warrants to purchase shares of Stock or any securities that are convertible into or exchangeable for, or that represent the right to receive, Stock or any such substantially similar securities (other than pursuant to employee stock option plans existing on, or upon the conversion or exchange of convertible or exchangeable securities outstanding as of, the date of this Agreement), without the prior written consent of William Blair & Company, L.L.C.; provided, however, that if (1) during the last 17 days of the initial Lock-Up Period, the Company releases earnings results or announces material news or a material event or (2) prior to the expiration of the initial Lock-Up Period, the Company announces that it will release earnings results during the 15-day period following the last day of the initial Lock-Up Period, then in each case the Lock-Up Period will be automatically extended until the expiration of the 18-day period beginning on the date of release of the earnings results or the announcement of the material news or material event, as applicable, unless William Blair & Company, L.L.C. waives, in writing, such extension; provided that the foregoing restrictions shall not apply to the issuance of securities of the Company (“Acquisition Securities”) in an amount up to an aggregate of 5% of the sum of the Company’s fully-diluted shares of Stock outstanding as of the date of the Prospectus and the Shares to be sold by the Company offered hereby, in exchange for the assets or equity of another entity in connection with the acquisition by the Company of, or joint venture with, such entity, provided, however, that the recipient of any such Acquisition Securities shall agree in writing to be bound by the terms of this Section 5(e); the Company will provide William Blair & Company, L.L.C. and each stockholder subject to the Lock-Up Period pursuant to the lockup letters described in Section 8(i) with prior notice of any such announcement that gives rise to an extension of the Lock-up Period;

(f) To use the net proceeds received by it from the sale of the Shares pursuant to this Agreement in the manner specified in the Pricing Prospectus under the caption “Use of Proceeds”;

(g) To use its reasonable best efforts to list, subject to notice of issuance, the Shares on the New York Stock Exchange (the “Exchange”);

(h) If the Company elects to rely upon Rule 462(b), the Company shall file a Rule 462(b) Registration Statement with the Commission in compliance with Rule 462(b) by 10:00 P.M., Washington, D.C. time, on the date of this Agreement, and the Company shall at the time of filing either pay to the Commission the filing fee for the Rule 462(b) Registration Statement or give irrevocable instructions for the payment of such fee pursuant to Rule 111(b) under the Act; and

(i) Upon the reasonable request of any Underwriter, to furnish, or cause to be furnished, to such Underwriter an electronic version of the Company’s trademarks, servicemarks and corporate logo for use on the website, if any, operated by such Underwriter for the purpose of facilitating the on-line offering of the Shares (the “License”); provided, however, that the License shall be used solely for the purpose described above, is granted without any fee and may not be assigned, transferred or sublicensed, and shall terminate when all the Shares offered on-line have been sold by such Underwriter.

6. The Company agrees with each Underwriter that:

(a) Without the prior consent of William Blair & Company, L.L.C., it has not made and will not make any offer relating to the Shares that would constitute a “free writing prospectus” as defined in Rule 405 under the Act; each Underwriter represents and agrees that, without the prior consent of the Company and William Blair & Company, L.L.C., it has not made and will not make any offer relating to the Shares that would constitute a free writing prospectus; any such free writing prospectus the use of which has been consented to by the Company and William Blair & Company, L.L.C. is listed on Schedule III(b) hereto;

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(b) The Company has complied and will comply with the requirements of Rule 433 under the Act applicable to any Issuer Free Writing Prospectus, including timely filing with the Commission or retention where required and legending; and the Company represents that it has satisfied and agrees that it will satisfy the conditions under Rule 433 under the Act to avoid a requirement to file with the Commission any electronic road show; and

(c) If at any time following issuance of an Issuer Free Writing Prospectus any event occurred or occurs as a result of which such Issuer Free Writing Prospectus would conflict with the information in the Registration Statement, the Pricing Prospectus or the Prospectus or would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances then prevailing, not misleading, the Company will give prompt notice thereof to William Blair & Company, L.L.C. and, if requested by William Blair & Company, L.L.C., will prepare and furnish without charge to each Underwriter an Issuer Free Writing Prospectus or other document which will correct such conflict, statement or omission; provided, however, that this covenant shall not apply to any statements or omissions in an Issuer Free Writing Prospectus made in reliance upon and in conformity with the Underwriter Information.

7. The Company and each of the Selling Stockholders covenant and agree with one another and with the several Underwriters that (a) the Company will pay or cause to be paid the following: (i) the fees, disbursements and expenses of the Company’s counsel and accountants in connection with the registration of the Shares under the Act and all other expenses in connection with the preparation, printing, reproduction and filing of the Registration Statement, any Preliminary Prospectus, any Issuer Free Writing Prospectus and the Prospectus and amendments and supplements thereto and the mailing and delivering of copies thereof to the Underwriters and dealers; (ii) the cost of printing or producing any of this Agreement, the Blue Sky Memorandum, closing documents (including any compilations thereof) and any other documents in connection with the offering, purchase, sale and delivery of the Shares; (iii) all expenses in connection with the qualification of the Shares for offering and sale under state securities laws as provided in Section 5(b) hereof, including the fees and disbursements of counsel for the Underwriters, which disbursement shall not exceed $7,500, in connection with such qualification and in connection with the Blue Sky survey; (iv) all fees and expenses in connection with listing the Shares on the Exchange; (v) the filing fees incident to, and the reasonable fees and disbursements of counsel for the Underwriters, which disbursement shall not exceed $25,000, in connection with, securing any required review by the FINRA of the terms of the sale of the Shares; (vi) the preparation, printing and distribution of one or more versions of the Preliminary Prospectus and the Prospectus for distribution in Canada, in the form of a Canadian “wrapper” (including related fees and disbursements of Canadian counsel to the Underwriters, which disbursement shall not exceed $10,000); (vii) the fees, disbursements and expenses of Latham & Watkins LLP, counsel to the Selling Stockholders, (viii) the cost of preparing stock certificates; (ix) the cost and charges of any transfer agent or registrar, the Custodian and the Attorneys-in-Fact; and (x) all other costs and expenses incident to the performance of its obligations hereunder which are not otherwise specifically provided for in this Section; and (b) such Selling Stockholder will pay or cause to be paid all costs and expenses incident to the performance of such Selling Stockholder’s obligations hereunder which are not otherwise specifically provided for in this Section, including (i) any fees and expenses of counsel or other advisors for such Selling Stockholder other than Latham & Watkins LLP, and (ii) all expenses (other than such expenses paid by the Company pursuant to (a) above) and taxes incident to the sale and delivery of the Shares to be sold by such Selling Stockholder to the Underwriters hereunder. It is understood, however, that, except as provided in this Section and Sections 9 and 12 hereof, in connection with hosting meetings with prospective purchasers of the Shares and investor presentations on any “road show” undertaken in connection with the marketing of the offering of the Shares, (i) the Company and the Underwriters will each pay fifty percent (50%) of the cost of any aircraft chartered or otherwise used in connection with such meetings, presentations and the road show and (ii) the Company and the Underwriters will each pay their own costs associated with hotel accommodations and any other costs and expenses. In connection with clause (b)(ii) of the preceding sentence, William Blair & Company, L.L.C. agrees to pay New York State stock transfer tax, and the Selling Stockholder agrees to reimburse William Blair & Company, L.L.C. for associated carrying costs if such tax payment is not rebated on the day of payment and for any portion of such tax payment not rebated. It is understood, however, that the Company shall bear, and the Selling Stockholders shall not be required to pay or to reimburse the Company for, the cost of any other matters not directly relating to the sale and purchase of the Shares pursuant to this Agreement, and that, except as provided in this Section, and Sections 9 and 12 hereof, the Underwriters will pay all of their own costs and expenses, including without limitation the fees of their counsel, stock transfer taxes on resale of any of the Shares by them, and any advertising expenses connected with any offers they may make.

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8. The obligations of the Underwriters hereunder, as to the Shares to be delivered at each Time of Delivery, shall be subject, in their discretion, to the condition that all representations and warranties and other statements of the Company and, with respect to the First Time of Delivery, of the Selling Stockholders, herein are, at and as of such Time of Delivery, true and correct, the condition that the Company and the Selling Stockholders shall have performed all of its and their respective obligations hereunder theretofore to be performed, and the following additional conditions:

(a) The Prospectus shall have been filed with the Commission pursuant to Rule 424(b) under the Act within the applicable time period prescribed for such filing by the rules and regulations under the Act and in accordance with Section 5(a) hereof; all material required to be filed by the Company pursuant to Rule 433(d) under the Act shall have been filed with the Commission within the applicable time period prescribed for such filing by Rule 433; if the Company has elected to rely upon Rule 462(b) under the Act, the Rule 462(b) Registration Statement shall have become effective by 10:00 P.M., Washington, D.C. time, on the date of this Agreement; no stop order suspending the effectiveness of the Registration Statement or any part thereof shall have been issued and no proceeding for that purpose shall have been initiated or threatened by the Commission; no stop order suspending or preventing the use of the Prospectus or any Issuer Free Writing Prospectus shall have been initiated or threatened by the Commission; and all requests for additional information on the part of the Commission shall have been complied with to your reasonable satisfaction;

(b) Wilson Sonsini Goodrich & Rosati, Professional Corporation, counsel for the Underwriters, shall have furnished to you such written opinion or opinions (a form of each such opinion is attached as Annex II(a) hereto), dated such Time of Delivery, in form and substance satisfactory to you, with respect to such matters as you may reasonably request, and such counsel shall have received such papers and information as they may reasonably request to enable them to pass upon such matters;

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(c) Latham & Watkins LLP, counsel for the Company and the Selling Stockholders, shall have furnished to you their written opinions (drafts of such opinions are attached as Annex II(b) hereto), dated such Time of Delivery, in form and substance satisfactory to you.

(d) Richards, Layton & Finger, P.A., counsel for the Company, shall have furnished to you their written opinion (a draft of such opinion is attached as Annex II(c) hereto), dated the First Time of Delivery, in form and substance satisfactory to you.

(e) On the date of the Prospectus at a time prior to the execution of this Agreement, at 9:30 a.m., New York City time, on the effective date of any post-effective amendment to the Registration Statement filed subsequent to the date of this Agreement and also at each Time of Delivery, Grant Thornton LLP shall have furnished to you a letter or letters, dated the respective dates of delivery thereof, the executed copy of the letter delivered prior to the execution of this Agreement is attached as Annex I(a) hereto (and a draft of the form of letter to be delivered on the effective date of any post-effective amendment to the Registration Statement and as of each Time of Delivery is attached as Annex I(a)(i) hereto);

(f) (i) The Company and its subsidiaries, taken as a whole, shall not have sustained since the date of the latest audited financial statements included in the Pricing Prospectus any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, in each case otherwise than as set forth or contemplated in the Pricing Disclosure Package, and (ii) since the respective dates as of which information is given in the Pricing Prospectus, there shall not have been any change in the capital stock or long-term debt of the Company and its subsidiaries, taken as a whole, or any change, or any development involving a prospective change, in or affecting the general affairs, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries, taken as a whole, otherwise than as set forth or contemplated in the Pricing Disclosure Package, the effect of which, in any such case described in clause (i) or (ii), is in your judgment so material and adverse as to make it impracticable or inadvisable to proceed with the public offering or the delivery of the Shares being delivered at such Time of Delivery on the terms and in the manner contemplated in the Prospectus;

(g) On or after the Applicable Time there shall not have occurred any of the following: (i) a suspension or material limitation in trading in securities generally on the Exchange; (ii) a suspension or material limitation in trading in the Company’s securities on the Exchange; (iii) a general moratorium on commercial banking activities declared by either Federal or New York State authorities or a material disruption in commercial banking or securities settlement or clearance services in the United States; (iv) the outbreak or escalation of hostilities involving the United States or the declaration by the United States of a national emergency or war or (v) the occurrence of any other calamity or crisis or any change in financial, political or economic conditions in the United States or elsewhere, if the effect of any such event specified in clause (iv) or (v) in your judgment makes it impracticable or inadvisable to proceed with the public offering or the delivery of the Shares being delivered at such Time of Delivery on the terms and in the manner contemplated in the Prospectus;

(h) The Shares to be sold at such Time of Delivery shall have been duly listed, subject to notice of issuance, on the Exchange;

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(i) The Company shall have obtained and delivered to the Underwriters executed copies of agreements, substantially to the effect set forth in Section 5(e) hereof in form and substance satisfactory to you, from each of the parties listed on Schedule IV hereto;

(j) The Company shall have complied with the provisions of Section 5(c) hereof with respect to the furnishing of copies of the Prospectus on the second New York Business Day next succeeding the date of this Agreement; and

(k) The Company and the Selling Stockholders shall have furnished or caused to be furnished to you at such Time of Delivery certificates of officers of the Company and of the Selling Stockholders, respectively, reasonably satisfactory to you as to the accuracy of the representations and warranties of the Company and the Selling Stockholders, respectively, herein at and as of such Time of Delivery, as to the performance by the Company and the Selling Stockholders of all of their respective obligations hereunder to be performed at or prior to such Time of Delivery, and as to such other matters as you may reasonably request, and the Company shall have furnished or caused to be furnished certificates as to the matters set forth in subsections (a) and (e) of this Section.

9. (a) The Company and each of the Management Selling Stockholders, jointly and severally, will indemnify and hold harmless each Underwriter against any losses, claims, damages or liabilities, joint or several, to which such Underwriter may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained or incorporated by reference in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, any Issuer Free Writing Prospectus or any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Act, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and will reimburse each Underwriter for any legal or other expenses reasonably incurred by such Underwriter in connection with investigating or defending any such action or claim as such expenses are incurred; provided, however, that the Company and the Management Selling Stockholders shall not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with the Underwriter Information or the Selling Stockholder Information.

(b) Each of the Selling Stockholders (other than the Management Selling Stockholders), severally and not jointly, will indemnify and hold harmless each Underwriter against any losses, claims, damages or liabilities, joint or several, to which such Underwriter may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with written information furnished to the Company by such Selling Stockholder expressly for use therein; and will reimburse each Underwriter for any legal or other expenses reasonably incurred by such Underwriter in connection with investigating or defending any such action or claim as such expenses are incurred; provided, however, that such Selling Stockholder shall not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in any Preliminary Prospectus, the Registration Statement or the Prospectus or any such amendment or supplement in reliance upon and in conformity with the Underwriter Information; provided, further, that the liability of such Selling Stockholders pursuant to this subsection (b) shall not exceed the product of the number of Shares sold by such Selling Stockholder and the “Offering proceeds to selling stockholders, before expenses” per Share as set forth in the cover page of the Prospectus (the “Selling Stockholder Proceeds”).

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(c) Each Underwriter will indemnify and hold harmless the Company and each Selling Stockholder against any losses, claims, damages or liabilities to which the Company or such Selling Stockholder may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with the Underwriter Information furnished to the Company by such Underwriter through William Blair & Company, L.L.C. expressly for use therein; and will reimburse the Company and each Selling Stockholder for any legal or other expenses reasonably incurred by the Company or such Selling Stockholder in connection with investigating or defending any such action or claim as such expenses are incurred.

(d) Promptly after receipt by an indemnified party under subsection (a), (b) or (c) above of notice of the commencement of any action, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under such subsection, notify the indemnifying party in writing of the commencement thereof; but the omission so to notify the indemnifying party shall not relieve it from any liability which it may have to any indemnified party otherwise than under such subsection. In case any such action shall be brought against any indemnified party and it shall notify the indemnifying party of the commencement thereof, the indemnifying party shall be entitled to participate therein and, to the extent that it shall wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel reasonably satisfactory to such indemnified party (who shall not, except with the consent of the indemnified party, be counsel to the indemnifying party), and, after notice from the indemnifying party to such indemnified party of its election so to assume the defense thereof, the indemnifying party shall not be liable to such indemnified party under such subsection for any legal expenses of other counsel or any other expenses, in each case subsequently incurred by such indemnified party, in connection with the defense thereof other than reasonable costs of investigation. No indemnifying party shall, without the written consent of the indemnified party, effect the settlement or compromise of, or consent to the entry of any judgment with respect to, any pending or threatened action or claim in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified party is an actual or potential party to such action or claim) unless such settlement, compromise or judgment (i) includes an unconditional release of the indemnified party from all liability arising out of such action or claim and (ii) does not include a statement as to or an admission of fault, culpability or a failure to act, by or on behalf of any indemnified party.

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(e) If the indemnification provided for in this Section 9 is unavailable to or insufficient to hold harmless an indemnified party under subsection (a), (b) or (c) above in respect of any losses, claims, damages or liabilities (or actions in respect thereof) referred to therein, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages or liabilities (or actions in respect thereof) in such proportion as is appropriate to reflect the relative benefits received by the Company and the Selling Stockholders on the one hand and the Underwriters on the other from the offering of the Shares. If, however, the allocation provided by the immediately preceding sentence is not permitted by applicable law or if the indemnified party failed to give the notice required under subsection (d) above, then each indemnifying party shall contribute to such amount paid or payable by such indemnified party in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company and the Selling Stockholders on the one hand and the Underwriters on the other in connection with the statements or omissions which resulted in such losses, claims, damages or liabilities (or actions in respect thereof), as well as any other relevant equitable considerations. The relative benefits received by the Company and the Selling Stockholders on the one hand and the Underwriters on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company and the Selling Stockholders bear to the total underwriting discounts and commissions received by the Underwriters, in each case as set forth in the table on the cover page of the Prospectus. The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Selling Stockholders on the one hand or the Underwriters on the other and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company, each of the Selling Stockholders and the Underwriters agree that it would not be just and equitable if contribution pursuant to this subsection (e) were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to above in this subsection (e). The amount paid or payable by an indemnified party as a result of the losses, claims, damages or liabilities (or actions in respect thereof) referred to above in this subsection (e) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this subsection (e), (i) no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Shares underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages which such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission and (ii) no Selling Stockholder shall be required to contribute any amount in excess of the amount by which the Selling Stockholder Proceeds exceed the amount of any damages that such Selling Stockholder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this subsection (e) to contribute are several in proportion to their respective underwriting obligations and not joint.

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(f) The obligations of the Company and the Selling Stockholders under this Section 9 shall be in addition to any liability which the Company and the respective Selling Stockholders may otherwise have and shall extend, upon the same terms and conditions, to each person, if any, who controls any Underwriter within the meaning of the Act and each broker-dealer affiliate of any Underwriter; and the obligations of the Underwriters under this Section 9 shall be in addition to any liability which the respective Underwriters may otherwise have and shall extend, upon the same terms and conditions, to each officer and director of the Company and to each person, if any, who controls the Company or any Selling Stockholder within the meaning of the Act.

(g) Notwithstanding anything to contrary in this Agreement, the aggregate liability of any Selling Stockholder under this Section 9 (including Section 9(a), (b), (e) and (f)) and/or otherwise pursuant to this Agreement shall not exceed the Selling Stockholder Proceeds received by such Selling Stockholder pursuant to this Agreement.

10. (a) If any Underwriter shall default in its obligation to purchase the Shares which it has agreed to purchase hereunder at a Time of Delivery, you may in your discretion arrange for you or another party or other parties to purchase such Shares on the terms contained herein. If within thirty-six hours after such default by any Underwriter you do not arrange for the purchase of such Shares, then the Company and the Selling Stockholders shall be entitled to a further period of thirty-six hours within which to procure another party or other parties satisfactory to you to purchase such Shares on such terms. In the event that, within the respective prescribed periods, you notify the Company and the Selling Stockholders that you have so arranged for the purchase of such Shares, or the Company or the Selling Stockholders notify you that they have so arranged for the purchase of such Shares, you or the Company and the Selling Stockholders shall have the right to postpone such Time of Delivery for a period of not more than seven days, in order to effect whatever changes may thereby be made necessary in the Registration Statement or the Prospectus, or in any other documents or arrangements, and the Company agrees to file promptly any amendments or supplements to the Registration Statement or the Prospectus which in your opinion may thereby be made necessary. The term “Underwriter” as used in this Agreement shall include any person substituted under this Section with like effect as if such person had originally been a party to this Agreement with respect to such Shares.

(b) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by you and the Company and the Selling Stockholders as provided in subsection (a) above, the aggregate number of such Shares which remains unpurchased does not exceed one-eleventh of the aggregate number of all the Shares to be purchased at such Time of Delivery, then the Company and the Selling Stockholders shall have the right to require each non-defaulting Underwriter to purchase the number of Shares which such Underwriter agreed to purchase hereunder at such Time of Delivery and, in addition, to require each non-defaulting Underwriter to purchase its pro rata share (based on the number of Shares which such Underwriter agreed to purchase hereunder) of the Shares of such defaulting Underwriter or Underwriters for which such arrangements have not been made; but nothing herein shall relieve a defaulting Underwriter from liability for its default.

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(c) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by you and the Company and the Selling Stockholders as provided in subsection (a) above, the aggregate number of such Shares which remains unpurchased exceeds one-eleventh of the aggregate number of all of the Shares to be purchased at such Time of Delivery, or if the Company and the Selling Stockholders shall not exercise the right described in subsection (b) above to require non-defaulting Underwriters to purchase Shares of a defaulting Underwriter or Underwriters, then this Agreement (or, with respect to the Second Time of Delivery, the obligations of the Underwriters to purchase and of the Company to sell the Optional Shares) shall thereupon terminate, without liability on the part of any non-defaulting Underwriter or the Company or the Selling Stockholders, except for the expenses to be borne by the Company and the Selling Stockholders and the Underwriters as provided in Section 7 hereof and the indemnity and contribution agreements in Section 9 hereof; but nothing herein shall relieve a defaulting Underwriter from liability for its default.

11. The respective indemnities, agreements, representations, warranties and other statements of the Company, the Selling Stockholders and the several Underwriters, as set forth in this Agreement or made by or on behalf of them, respectively, pursuant to this Agreement, shall remain in full force and effect, regardless of any investigation (or any statement as to the results thereof) made by or on behalf of any Underwriter or any controlling person of any Underwriter, or the Company, or any of the Selling Stockholders, or any officer or director or controlling person of the Company, or any controlling person of any Selling Stockholder, and shall survive delivery of and payment for the Shares.

12. If this Agreement shall be terminated pursuant to Section 10 hereof, neither the Company nor the Selling Stockholders shall then be under any liability to any Underwriter except as provided in Sections 7 (subject to the last sentence of this Section 12) and 9 hereof; but, if for any other reason any Shares are not delivered by or on behalf of the Company and the Selling Stockholders as provided herein, the Company and each of the Selling Stockholders pro rata (based on the number of Shares to be sold by the Company and such Selling Stockholder hereunder) will reimburse the Underwriters through you for all out-of-pocket expenses approved in writing by you, including fees and disbursements of counsel, reasonably incurred by the Underwriters in making preparations for the purchase, sale and delivery of the Shares not so delivered, but the Company and the Selling Stockholders shall then be under no further liability to any Underwriter in respect of the Shares not so delivered except as provided in Sections 7 and 9 hereof. If this Agreement is terminated pursuant to Section 10 by reason of the default of one or more Underwriters, neither the Company nor any Selling Shareholder shall be obligated to reimburse any defaulting Underwriter on account of those expenses.

13. In all dealings hereunder, you shall act on behalf of each of the Underwriters, and the parties hereto shall be entitled to act and rely upon any statement, request, notice or agreement on behalf of any Underwriter made or given by the Representative; and in all dealings with any Selling Stockholder hereunder, you and the Company shall be entitled to act and rely upon any statement, request, notice or agreement on behalf of such Selling Stockholder made or given by any or all of the Attorneys-in-Fact for such Selling Stockholder.

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All statements, requests, notices and agreements hereunder shall be in writing, and if to the Underwriters shall be delivered or sent by mail, nationally recognized overnight courier, telex or facsimile transmission to you as the Representative in care of William Blair & Company, L.L.C., 222 West Adams Street, Chicago, IL 60606, Attention: General Counsel; if to any Selling Stockholder shall be delivered or sent by mail or facsimile transmission with a copy sent by E-mail to counsel for such Selling Stockholder at its address set forth in Schedule II hereto; and if to the Company shall be delivered or sent by mail, nationally recognized overnight courier, or facsimile transmission with a copy sent by E-mail to the address of the Company set forth in the Registration Statement, Attention: General Counsel, with a copy to Latham & Watkins LLP, 140 Scott Drive, Menlo Park, California 94025, Attention: Christopher L. Kaufman; provided, however, that any notice to an Underwriter pursuant to Section 9(d) hereof shall be delivered or sent by mail, nationally recognized overnight courier, telex or facsimile transmission to such Underwriter at its address set forth in its Underwriters’ Questionnaire or telex constituting such Questionnaire, which address will be supplied to the Company or the Selling Stockholders by you upon request; provided, however, that notices under subsection 5(e) to any person who has delivered an executed agreement pursuant to subsection 8(i) shall be delivered or sent by mail, nationally recognized overnight courier, telex or facsimile transmission to such person at its address set forth in Schedule V hereto. Any such statements, requests, notices or agreements shall take effect upon receipt thereof.

In accordance with the requirements of the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), the Underwriters are required to obtain, verify and record information that identifies their respective clients, including the Company, which information may include the name and address of their respective clients, as well as other information that will allow the Underwriters to properly identify their respective clients.

14. This Agreement shall be binding upon, and inure solely to the benefit of, the Underwriters, the Company and the Selling Stockholders and, to the extent provided in Sections 9 and 11 hereof, the officers and directors of the Company and each person who controls the Company, any Selling Stockholder or any Underwriter, and their respective heirs, executors, administrators, successors and assigns, and no other person shall acquire or have any right under or by virtue of this Agreement. No purchaser of any of the Shares from any Underwriter shall be deemed a successor or assign by reason merely of such purchase.

15. Time shall be of the essence of this Agreement. As used herein, the term “business day” shall mean any day when the Commission’s office in Washington, DC is open for business.

16. The Company and each Selling Stockholder acknowledges and agrees that (i) the purchase and sale of the Shares pursuant to this Agreement is an arm’s-length commercial transaction between the Company and such Selling Stockholder, on the one hand, and the several Underwriters, on the other, (ii) in connection therewith and with the process leading to such transaction each Underwriter is acting solely as a principal and not the agent or fiduciary of the Company or such Selling Stockholder, (iii) no Underwriter has assumed an advisory or fiduciary responsibility in favor of the Company or such Selling Stockholder with respect to the offering contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company or such Selling Stockholder on other matters) or any other obligation to the Company or such Selling Stockholder except the obligations expressly set forth in this Agreement and (iv) the Company and such Selling Stockholder has consulted its own legal and financial advisors to the extent it deemed appropriate. The Company and each Selling Stockholder agrees that it will not claim that the Underwriters, or any of them, has, in connection with the transactions contemplated hereby, rendered advisory services of any nature or respect, or owes a fiduciary or similar duty to the Company or such Selling Stockholder, in connection with such transaction or the process leading thereto.

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17. This Agreement supersedes all prior agreements and understandings (whether written or oral) between or among the Company, the Selling Stockholders and the Underwriters, or any of them, with respect to the subject matter hereof.

18. THIS AGREEMENT AND ANY MATTERS RELATED TO THIS TRANSACTION SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF LAWS THAT WOULD RESULT IN THE APPLICATION OF ANY LAW OTHER THAN THE LAWS OF THE STATE OF NEW YORK. The Company agrees that any suit or proceeding arising in respect of this agreement or our engagement will be tried exclusively in the U.S. District Court for the Southern District of New York or, if that court does not have subject matter jurisdiction, in any state court located in The City and County of New York and the Company agrees to submit to the jurisdiction of, and to venue in, such courts.

19. The Company and each of the Underwriters hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

20. This Agreement may be executed by any one or more of the parties hereto in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same instrument.

21. Notwithstanding anything herein to the contrary, the Company and the Selling Stockholders are authorized to disclose to any persons the U.S. federal and state income tax treatment and tax structure of the potential transaction and all materials of any kind (including tax opinions and other tax analyses) provided to the Company and the Selling Stockholders relating to that treatment and structure, without the Underwriters imposing any limitation of any kind. However, any information relating to the tax treatment and tax structure shall remain confidential (and the foregoing sentence shall not apply) to the extent necessary to enable any person to comply with securities laws. For this purpose, “tax structure” is limited to any facts that may be relevant to that treatment.

22. If any term or other provision of this Agreement shall be held invalid, illegal or unenforceable, the validity, legality or enforceability of the other provisions of this Agreement shall not be affected thereby, and there shall be deemed substituted for the provision at issue a valid, legal and enforceable provision as similar as possible to the provision at issue.

23. Except as otherwise expressly provided herein, the provisions of this Agreement may be amended or waived at any time only by the written agreement of the parties hereto. Any waiver, permit, consent or approval of any kind or character on the part of any such holders of any provision or condition of this Agreement must be made in writing and shall be effective only to the extent specifically set forth in writing. The failure of any party hereto to enforce at any time any provision of this Agreement shall not be construed to be a waiver of such provision, nor in any way to affect the validity of this Agreement or any part hereof or the right of any party thereafter to enforce each and every such provision. No waiver of any breach of this Agreement shall be held to constitute a waiver of any other or subsequent breach.

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24. When this Agreement is executed by a trustee of a trust, in his or her capacity as trustee, or by an Attorney-in-Fact on behalf of a trustee of a trust, in his or her capacity as trustee, such execution is by or on behalf of the trustee, not individually, but solely as trustee in the exercise of and under the power and authority conferred upon and invested in such trustee, and it is expressly understood and agreed that nothing contained in this Agreement shall be construed as imposing any liability on any such trustee, in his or her capacity as trustee, personally for breaches of any representations or warranties made hereunder, or personally to pay any amounts required to be paid hereunder, or personally to perform any covenant, either express or implied, contained herein, all such personal liability of such trustee, in his or her capacity as trustee, if any, having been expressly waived by the parties by their execution hereof. Any liability of a trust hereunder shall not be a personal liability of any trustee, grantor or beneficiary thereof, and any recourse against a trustee, in his or her capacity as trustee, shall be solely against the assets of the pertinent trust.

If the foregoing is in accordance with your understanding, please sign and return to us six counterparts hereof, and upon the acceptance hereof by you, on behalf of each of the Underwriters, this letter and such acceptance hereof shall constitute a binding agreement among each of the Underwriters, the Company and each of the Selling Stockholders. It is understood that your acceptance of this letter on behalf of each of the Underwriters is pursuant to the authority set forth in a form of Agreement among Underwriters, the form of which shall be submitted to the Company and the Selling Stockholders for examination, upon request, but without warranty on your part as to the authority of the signers thereof.

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Any person executing and delivering this Agreement as Attorney-in-Fact for a Selling Stockholder represents by so doing that he has been duly appointed as Attorney-in-Fact by such Selling Stockholder pursuant to a validly existing and binding Power-of-Attorney which authorizes such Attorney-in-Fact to take such action.

[Signature page to Underwriting Agreement]

On behalf of each of the Underwriters

[Signature page to Underwriting Agreement]

SCHEDULE I

SCHEDULE II

Latham & Watkins LLP

140 Scott Drive

Menlo Park, CA 94025

Facsimile: (650)  ###-###-####

Attention: Robert W. Phillips

SCHEDULE IIa

Jonathan Corr

Edgar Luce

SCHEDULE III

SCHEDULE IV

Lock-Up Agreement Signatories:

A. Barr Dolan

Alan S. Henricks

Bernard M. Notas

Carl Buccellato and Mary Ellen Buccellato

Craig S. Davis

Edgar A. Luce

Elisa Lee

Frank J. Schultz

Jeb S. Spencer

Jonathan H. Corr

Limun Hu and Christine Hu

Notas Family Trust

Robert J. Levin

Sigmund and Susan Anderman Family Trust

Sigmund Anderman