Zipcar, Inc. Common Stock ($0.001 par value per share) Underwriting Agreement

Exhibit 1.1

Zipcar, Inc.

Common Stock ($0.001 par value per share)

Underwriting Agreement

                    , 2011

Goldman, Sachs & Co.

J.P. Morgan Securities LLC

As representatives of the several Underwriters

named in Schedule I hereto

c/o Goldman, Sachs & Co.

200 West Street

New York, New York 10282

c/o J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Ladies and Gentlemen:

Zipcar, 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”) an aggregate of                      shares of Common Stock, par value $0.001 per share (“Stock”), of the Company and, at the election of the Underwriters, up to                      additional shares of Stock of the Company, and the stockholders of the Company named in Schedule V hereto (the “Selling Stockholders”) propose, subject to the terms and conditions stated herein, to sell, severally and not jointly, to the Underwriters an aggregate of                      shares of Stock of the Company and, at the election of the Underwriters, up to                      additional shares of Stock of the Company. The aggregate of                      shares of Stock to be sold by the Company and the Selling Stockholders is herein called the “Firm Shares” and the aggregate of up to                      additional shares of Stock to be sold by the Company and the Selling Stockholders at the election of the Underwriters 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 represents and warrants to, and agrees with, each of the Underwriters that:

(i) A registration statement on Form S-1 (File No. 333-167220) (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, 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 confidential treatment requests filed pursuant to Rule 406 under the Act, no other document with respect to the Initial Registration Statement 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 Company’s knowledge, threatened by the Commission (any preliminary prospectus included in the Initial Registration Statement or filed with the Commission pursuant to Rule 424(a) of the rules and regulations of the Commission under the Act 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 the information contained in the form of final prospectus 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 430A under the Act to be part of the Initial Registration Statement at the time it was declared 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 last 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)(iii) hereof) is hereinafter called the “Pricing Prospectus”; and such final prospectus, in the form first filed pursuant to Rule 424(b) under the Act, is hereinafter called the “Prospectus”; and any “issuer free writing prospectus” as defined in Rule 433 under the Act relating to the Shares is hereinafter called an “Issuer Free Writing Prospectus”);

(ii) 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

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circumstances under which they were made, 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 information furnished in writing to the Company by an Underwriter through Goldman, Sachs & Co. or J.P. Morgan Securities LLC (collectively, the “Representatives”) expressly for use therein or by a Selling Stockholder expressly for use in the preparation of the answers therein to Items 7 and 11(m) of Form S-1;

(iii) For the purposes of this Agreement, the “Applicable Time” is         :                 .m. (Eastern time) on the date of this Agreement. The Pricing Prospectus, as supplemented by (A) each Issuer Free Writing Prospectus and any other documents listed on Schedule III(a) hereto and (B) the pricing information set forth on Schedule III(c) hereto, taken together (collectively, 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(a) or Schedule III(b) hereto does not conflict with the information contained in the Registration Statement, the Pricing Prospectus or the Prospectus and each such Issuer Free Writing Prospectus, as supplemented by and taken together with the Pricing Prospectus as of the Applicable Time, did not include any untrue statement of a material fact or, when taken together with the Pricing Disclosure Package, 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 an Issuer Free Writing Prospectus in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein or by a Selling Stockholder expressly for use in the preparation of the answers therein to Items 7 and 11(m) of Form S-1;

(iv) The Registration Statement conforms, and the Prospectus and any further amendments or supplements to the Registration Statement and 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 information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein or by a Selling Stockholder expressly for use in the preparation of the answers therein to Items 7 and 11(m) of Form S-1;

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(v) Neither the Company nor any of its subsidiaries has sustained since the date of the latest audited financial statements included in the Pricing Prospectus any material loss or interference with the business of the Company and its subsidiaries, taken as a whole, 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, otherwise than as set forth or contemplated in the Pricing Prospectus; and, since the respective dates as of which information is given in the Registration Statement and the Pricing Prospectus, there has not been any change in the capital stock (other than as a result of the grant or exercise of an immaterial amount of stock options pursuant to the Company’s 2000 Stock Incentive Plan, 2010 Stock Incentive Plan or 2011 Stock Incentive Plan, as in effect on the date hereof and disclosed in the Pricing Prospectus (collectively, the “Company Incentive Plans”)) or long-term debt of the Company or any of its subsidiaries 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, otherwise than as set forth or contemplated in the Pricing Prospectus;

(vi) The Company and its subsidiaries have good and marketable title in fee simple to all real property and good and marketable title to all personal property owned by them, in each case free and clear of all liens, encumbrances and defects except such as are described in the Registration Statement or such as do not materially affect the value of such property and do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries; and any real property, buildings and vehicles 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 materially interfere with the use made and proposed to be made of such property, buildings and vehicles by the Company and its subsidiaries;

(vii) The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Delaware, with power and authority (corporate and other) to own its properties and conduct its business as described in the Pricing Prospectus, and 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, or is subject to no material liability or disability by reason of the failure to be so qualified in any such jurisdiction; and each subsidiary of the Company has been duly organized and is validly existing as a business entity in good standing under the laws of its jurisdiction of incorporation;

(viii) The Company has an authorized capitalization as set forth in the Pricing Prospectus and all of the issued shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-

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assessable and conform to the description of the Stock contained in the Pricing Prospectus and that will be contained in the Prospectus; and all of the issued shares of capital stock or membership interests, as applicable, of each subsidiary of the Company have been duly authorized and validly issued, are fully paid and non-assessable and (except for directors’ qualifying shares and the shares of Flexcar Atlanta, LLC owned by Midtown Lanier Parking, Inc.) are owned directly or indirectly by the Company, free and clear of all liens, encumbrances, equities or claims;

(ix) 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 to the description of the Stock contained in the Pricing Prospectus and Prospectus and the issuance of such Shares will not be subject to any preemptive or similar rights;

(x) The issue and sale of the Shares to be sold by the Company and the compliance by the Company with this Agreement and the consummation by the Company of the transactions herein contemplated (a) will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a 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, (b) will not violate (1) the provisions of the Certificate of Incorporation or By-laws of the Company or (2) 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, except, in the case of (a) or (b)(2) above, for conflicts, breaches or violations that would not, individually or in the aggregate, have a material adverse effect on the Company and its subsidiaries, taken as a whole; 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 the registration under the Act of the Shares and 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;

(xi) Neither the Company nor any of its subsidiaries is in violation of its Certificate of Incorporation or By-laws or in default in the performance or observance of any material 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;

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(xii) The statements set forth in the Pricing Prospectus and Prospectus under the caption “Description of Capital Stock”, insofar as they purport to constitute a summary of the terms of the Stock and under the captions “Underwriting” and “Material U.S. Federal Tax Considerations for non-U.S. Holders of Common Stock”, insofar as they purport to describe the provisions of the laws and documents referred to therein, are accurate and complete in all material respects;

(xiii) Other than as set forth in the Pricing Prospectus, 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 have a material adverse effect on the current or future financial position, stockholders’ equity or results of operations of the Company and its subsidiaries; and, to the best of the Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others;

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

(xv) 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;

(xvi) PricewaterhouseCoopers LLP and Baker Tilly, Virchow Krause, LLP, who have 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;

(xvii) The Company maintains a system of internal control over financial reporting (as such term is defined in Rule 13a-15(f) under the Securities Exchange Act of 1934, as amended (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. 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;

(xviii) 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 adversely affected, or is reasonably likely to materially adversely affect, the Company’s internal control over financial reporting;

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(xix) 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;

(xx) 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 to have such securities otherwise registered by the Company under the Act, except for rights that have been waived in writing, and except as described in the Registration Statement or the Pricing Prospectus;

(xxi) Except as described in the Pricing Prospectus or except where the failure of any of the following representations to be true would not reasonably be expected to have a material adverse effect on the Company and its subsidiaries, taken as a whole: (i) the Company and its subsidiaries own, possess, or have valid, binding and enforceable licenses or other rights to use the patents, patent rights and patent applications, copyrights, trademarks, service marks, trade names, Internet domain names, technology, confidential information, software, know-how, including (trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures) and other intellectual property and proprietary rights necessary or used in connection with the conduct of their business as currently conducted and in the manner set forth in the Pricing Prospectus (collectively, the “Company Intellectual Property”), and to the extent that the Company Intellectual Property is not sufficient to so conduct their business, including with respect to any products described in the Pricing Prospectus as being under development, the Company believes it can acquire such rights on reasonable terms; (ii) to the Company’s knowledge, none of the Company Intellectual Property owned by the Company or its subsidiaries is invalid or unenforceable and neither the Company nor any of its subsidiaries has received any challenge (including without limitation, notices of expiration) to the validity or enforceability thereof from any third party or governmental authority and the Company and its subsidiaries have made all filings and paid all fees necessary to maintain any Company Intellectual Property owned by any of them; (iii) the Company and its subsidiaries have taken reasonable measures necessary to secure their interests in Company Intellectual Property, including the confidentiality of all trade secrets and confidential information which constitutes Company Intellectual Property, and to secure assignment of Company Intellectual Property from its employees and contractors; (iv) the Company is not aware of any Company Intellectual Property required to be described in the Pricing

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Prospectus; (v) neither the Company nor any of its subsidiaries has received any notice of a claim of infringement or misappropriation of (and the Company does not know of any infringement or misappropriation of) intellectual property rights of others by the Company or any of its subsidiaries; (vi) to the Company’s knowledge, it and its subsidiaries are not in breach of, and have complied with all terms of, any license or other agreement relating to any Company Intellectual Property, except as would not reasonably be expected to have a material adverse effect on the Company and its subsidiaries, taken as a whole, and no party to any such agreement has given the Company or its subsidiaries notice of its intention to cancel, terminate, alter the scope of rights under or fail to renew any such agreement; and (vii) the Company is not aware of any suit or other proceeding pending against the Company or any of its subsidiaries concerning any agreement concerning the Company Intellectual Property, including any proceeding concerning a claim that the Company or its subsidiaries or another person has breached any such agreement;

(xxii) The Company and each of its subsidiaries are insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as are prudent and customary in the businesses in which they are engaged; neither the Company nor any of its subsidiaries has been refused any insurance coverage sought or applied for; and neither the Company nor any of its subsidiaries has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a material adverse effect on the Company and its subsidiaries, taken as a whole, except as described in the Pricing Prospectus;

(xxiii) The Company and its subsidiaries possess all certificates, authorizations and permits issued by the appropriate federal, state or foreign regulatory authorities necessary to conduct their respective businesses, and neither the Company nor any of its subsidiaries has received any written notice of proceedings relating to the revocation or modification of any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a material adverse effect on the Company and its subsidiaries, taken as a whole, except as described in the Pricing Prospectus;

(xxiv) The statistical and market-related data contained in the Pricing Prospectus are based on or derived from sources which the Company reasonably and in good faith believes are reliable and accurate, and such data agree with the sources from which they were derived;

(xxv) Except as described in the Pricing Prospectus, the Company and its subsidiaries are in compliance with, and conduct their respective businesses in conformity with, all applicable federal, state and local laws and regulations, except where the failure to so comply or conform would not reasonably be expected to

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have a material adverse effect on the Company and its subsidiaries, taken as a whole;

(xxvi) Neither the Company nor any of its subsidiaries, nor, to the Company’s knowledge, any other person associated with or acting on behalf of the Company or any of its subsidiaries, including, without limitation, any director, officer, agent or employee of the Company or any of its subsidiaries, has, while acting on behalf of the Company or any of its subsidiaries, (A) used any corporate funds for unlawful contributions, gifts, entertainment or other unlawful expenses relating to political activity; (B) made any direct or indirect unlawful payment to foreign or domestic government officials or employees from corporate funds; (C) made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment; or (D) taken any action that would result in a violation by such persons of any provision of the Foreign Corrupt Practices Act of 1977, as amended (the “FCPA”), and the rules and regulations thereunder; and the Company has instituted and maintains policies and procedures reasonably designed to ensure compliance therewith;

(xxvii) None of the Company, any of its subsidiaries or, to the Company’s knowledge, any director, officer, agent, affiliate or employee of the Company or any of its subsidiaries is currently subject to any 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 from the sale of the Shares by the Company, or lend, contribute or otherwise make available such proceeds to any subsidiary, affiliate, joint venture partner or other person or entity for the purpose of financing the activities of any person currently subject to any sanctions administered by OFAC; and

(xxviii) 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 where the Company and its subsidiaries conduct business, 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.

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

(i) Except for the registration under the Act of the Shares and such consents, approvals, authorizations and orders as may be required under any state securities, blue sky or antifraud laws, or FINRA in connection with the

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purchase and distribution of the Shares by the Underwriters, all consents, approvals, authorizations and orders necessary for the execution and delivery by or on behalf of such Selling Stockholder of this Agreement and the Power of Attorney and the Custody Agreement hereinafter referred to, and for the sale and delivery of the Shares to be sold by such Selling Stockholder hereunder, have been obtained, except for such consents, approvals, authorizations and orders as would not reasonably be expected to impair the consummation of such Selling Stockholder’s obligations hereunder; 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.

(ii) 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 (A) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any statute, 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, (B) result in any violation of the provisions of the Certificate of Incorporation or By-laws of such Selling Stockholder if such Selling Stockholder is a corporation, or the Partnership Agreement of such Selling Stockholder if such Selling Stockholder is a partnership, or (C) result in a violation of 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, except in the case of clause (A) or (C), for such conflicts, breaches, violations or defaults as would not reasonably be expected to impair the consummation of such Selling Stockholder’s obligations hereunder and thereunder;

(iii) Immediately prior to each Time of Delivery (as defined in Section 4 hereof) such Selling Stockholder will have, good and valid title to the Shares to be sold by such Selling Stockholder hereunder, free of any “adverse claim” (within the meaning of Section 8-102 of the Uniform Commercial Code as in effect in the State of New York (the “New York UCC”)); upon payment by the Underwriters for the Shares to be sold by such Selling Stockholder pursuant to this Agreement, delivery of such Shares, as directed by the Underwriters, to the Depository Trust Company (“DTC”) or its agent, registration of such Shares in the name of Cede & Co. (“Cede”) or such other nominee as may be designated by the DTC, and the crediting of such Shares on the records of DTC to securities accounts of the Underwriters (assuming that neither DTC nor any such Underwriter has notice of any adverse claim (within the meaning of Section 8-105 of the Uniform Commercial Code (“UCC”) to such Shares), (1) DTC will be a “protected purchaser” of such Shares within the meaning of Section 8-303 of the New York

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UCC, (2) under Section 8-501 of the UCC, the Underwriters will acquire a valid security entitlement in respect of such Shares and (3) no action based on any “adverse claim”, within the meaning of Section 8-102 of the UCC, to such Shares may be asserted against the Underwriters with respect to such security entitlement. For purposes of this representation, such Selling Stockholder may assume that when such payment, delivery and crediting occur, (A) such Shares will have been registered in the name of Cede or another nominee designated by DTC, in each case on the Company’s share registry in accordance with its certificate of incorporation, bylaws and applicable law, (B) DTC will be registered as a “clearing corporation” within the meaning of Section 8-102 of the UCC and (C) appropriate entries to the accounts of the several Underwriters on the records of DTC will have been made pursuant to the UCC;

(iv) Such Selling Stockholder has duly executed and delivered to the Company, for further delivery to the Underwriters, a lock-up agreement in the form attached as Exhibit A hereto;

(v) Such Selling Stockholder 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;

(vi) To the extent of any statements or omissions made in the Registration Statement, any Preliminary Prospectus, the Prospectus or 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, the Registration Statement and any such Issuer Free Writing Prospectus did not, and the Prospectus and any Issuer Free Writing Prospectus and any further amendments or supplements to the Registration Statement, the Prospectus, and any Issuer Free Writing Prospectus when they become effective or are filed with the Commission, as the case may be, 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 (in the case of the Preliminary Prospectus, the Pricing Prospectus, the Prospectus, or any amendment or supplement thereto, and any Issuer Free Writing Prospectus, in light of the circumstances under which they were made) it being acknowledged and agreed that the only written information provided by such Selling Stockholder consists of the information set forth in his or her or its responses to the Selling Stockholder questionnaire submitted to the Company in connection with public offering of the Shares (the “Selling Stockholder Information”);

(vii) 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 will deliver to you prior to or at the First Time of Delivery (as hereinafter defined) a

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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);

(viii) Certificates in negotiable form representing all of the Shares to be sold by such Selling Stockholder hereunder 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 the Company, 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 V 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 and otherwise to act on behalf of such Selling Stockholder in connection with the transactions contemplated by this Agreement and the Custody Agreement in accordance with the Power of Attorney; and

(ix) 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, except in the case of the Custody Agreement, as set forth therein; 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.

2. Subject to the terms and conditions herein set forth, the Company and each of the Selling Stockholders agree, severally and not jointly, to sell to each of

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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 $                     , the number of Firm Shares (to be adjusted by you so as to eliminate fractional shares) determined by multiplying the aggregate number of Shares to be sold by the Company and each of the Selling Stockholders as set forth opposite their respective names in Schedule V 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 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 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 and the Selling Stockholders, as and to the extent indicated in Schedule V hereto, hereby grant, severally and not jointly, to the Underwriters the right to purchase at their election up to                      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 shall be made in proportion to the maximum number of Optional Shares to be sold by the Company and each Selling Stockholder as set forth in Schedule V hereto initially with respect to the Optional Shares to be sold by the Company and then among the Selling Stockholders in proportion to the maximum number of Optional Shares to be sold by each Selling Stockholder as set forth in Schedule V hereto. Any such election to purchase Optional Shares may be exercised only by written notice from you to the Company and the Attorneys-in-Fact, 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

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defined in Section 4 hereof) or, unless you and the Company and the Attorneys-in-Fact 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 definitive form, and in such authorized denominations and registered in such names as the Representatives 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 the Representatives, through the facilities of the Depository Trust Company (“DTC”), 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 accounts specified by the Company and the Custodian for each of the Selling Stockholders, as their interests may appear, to the Representatives at least forty-eight hours in advance. The Company will cause the certificates representing the Shares to be made available for checking and packaging at least twenty-four hours prior to the Time of Delivery (as defined below) with respect thereto at the office of DTC or its designated custodian (the “Designated Office”). 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                     , 2011 or such other time and date as the Representatives, the Company and the Attorneys-in-Fact may agree upon in writing, and, with respect to the Optional Shares, 9:30 a.m., New York time, on the date specified by the Representatives in the written notice given by the Representatives of the Underwriters’ election to purchase such Optional Shares, or such other time and date as the Representatives, the Company and the Attorneys-in-Fact 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”.

(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(j) hereof, will be delivered at the offices of Ropes & Gray LLP, Prudential Tower, 800 Boylston Street, Boston, Massachusetts 02199 (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          p.m., New York City time, on the New York Business Day next 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

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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.

(c) The Company, in accordance with the requirements of NASD Conduct Rule 2720, as amended (“Rule 2720”), as administered by FINRA, and subject to the terms and conditions stated herein, hereby confirms the engagement of J.P. Morgan Securities LLC, and J.P. Morgan Securities LLC hereby confirms its agreement to render services, as a “qualified independent underwriter” within the meaning of Rule 2720(f)(12) in connection with the offering and sale of the Shares. J.P. Morgan Securities LLC, in its capacity as “qualified independent underwriter” and not otherwise, is referred to herein as the “Independent Underwriter.”

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, or, if applicable, such earlier time as may be required by Rule 430A(a)(3) under the Act; 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 disapproved by you promptly after reasonable notice thereof; 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; 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 best efforts to obtain the withdrawal of such order;

(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 reasonably 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 qualify as a foreign corporation or to file a general consent to service of process

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in any jurisdiction or to subject itself to taxation for doing business in any jurisdiction;

(c) Prior to 10:00 a.m., New York City time, on the 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 same period to amend or supplement the Prospectus in order to comply with the Act, to notify you and upon your request 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 as soon as practicable, but in any event not later than eighteen 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);

(e) During the initial Lock-Up Period, (i) not to offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose, except as provided hereunder, of 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), or (ii) file any registration statement with the Commission relating to the offering of any

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shares of Stock or any securities convertible into or exercisable or exchangeable for Stock (other than any registration statement on Form S-8), in each case without the prior written consent of the Representatives; 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 the Representatives waive, in writing, such extension; the Company will provide the Representatives 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;

The restrictions contained in the preceding paragraph shall not apply to (a) the Shares to be sold hereunder by the Company, (b) the issuance by the Company of shares of Stock upon the exercise of an option to purchase Stock granted under the Company Incentive Plans, the grant of options to purchase Stock and restricted stock awards to employees, consultants, advisors, officers or directors of the Company under the Company Incentive Plans, the issuance of shares of Stock upon exercise of a warrant, or the conversion of a security outstanding on the date hereof and described in the Preliminary Prospectus, or (c) the issuance of up to an aggregate of 5% of the shares of Stock to be outstanding immediately following the sale of the Shares pursuant to this Agreement in connection with a strategic acquisition by the Company or one or more of its subsidiaries of the assets or capital stock of another person or entity, whether through merger, asset acquisition, stock purchase or otherwise; provided, however, that in each case of (b) and (c) of this paragraph, the issuance of such shares of Stock by the Company be subject to the condition that each recipient of such shares has previously signed a lock-up agreement substantially to the effect set forth in Section 1(b)(iv) hereof.

(f) To furnish to its stockholders as soon as practicable after the end of each fiscal year an annual report (including a balance sheet and statements of income, stockholders’ equity and cash flows of the Company and its consolidated subsidiaries certified by independent public accountants) and, as soon as practicable after the end of each of the first three quarters of each fiscal year (beginning with the fiscal quarter ending after the effective date of the Registration Statement), to make available to its stockholders consolidated summary financial information of the Company and its subsidiaries for such quarter in reasonable detail;

(g) During a period of three years from the effective date of the Registration Statement, to furnish or make available to you copies of all reports or

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other communications (financial or other) furnished to stockholders, and to deliver to you (i) as soon as they are available and upon your request, copies of any current, periodic or annual reports and financial statements furnished to or filed with the Commission or any national securities exchange on which any class of securities of the Company is listed, other than those reports and financial statements that are available through the Commission’s Electronic Data Gathering Analysis Retrieval System (or any successor to such system); and (ii) such additional information concerning the business and financial condition of the Company as you may from time to time reasonably request (such financial statements to be on a consolidated basis to the extent the accounts of the Company and its subsidiaries are consolidated in reports furnished to its stockholders generally or to the Commission), provided that no such additional information shall be required except to the extent the disclosure of additional information would not result in a violation of Regulation FD (without requiring new disclosure to third parties in order to avoid violation of Regulation FD), provided further that the Company may satisfy the requirements of this paragraph by posting any such information on its website;

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

(i) To use its best efforts to list the Shares on The NASDAQ Global Market;

(j) To file with the Commission such information on Form 10-Q or Form 10-K as may be required by Rule 463 under the Act;

(k) 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

(l) Upon 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 or transferred.

6. (a) The Company represents and agrees that, without the prior consent of the Representatives, 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

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the prior consent of the Company and the Representatives, 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 the Representatives is listed on Schedule II(a) hereto;

(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;

(c) The Company agrees that 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 the Representatives and, if requested by the Representatives, 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 representation and warranty shall not apply to any statements or omissions in an Issuer Free Writing Prospectus made in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein.

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 Agreement among Underwriters, 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 reasonable fees and disbursements of counsel for the Underwriters in connection with such qualification and in connection with the Blue Sky survey

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(iv) all fees and expenses in connection with listing the Shares on NASDAQ; (v) the filing fees incident to, and the fees and disbursements (up to an aggregate of $20,000) of counsel for the Underwriters in connection with, any required review by the Financial Industry Regulatory Authority (“FINRA”) of the terms of the sale of the Shares; (vi) the cost of preparing stock certificates; (vii) the cost and charges of any transfer agent or registrar; (viii) the fees, disbursements and expenses of Edwards Angell Palmer & Dodge LLP, as counsel for the Selling Stockholders in connection with the offering; and (ix) 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 for such Selling Stockholder (other than the fees and expenses of Edwards Angell Palmer & Dodge LLP, counsel for the Selling Stockholders) and (ii) all expenses (but excluding any expenses of the Custodian) and taxes incident to the sale and delivery of the Shares to be sold by such Selling Stockholder to the Underwriters hereunder. In connection with clause (b)(ii) of the preceding sentence, Goldman, Sachs & Co. agrees to pay New York State stock transfer tax, and the Selling Stockholder agrees to reimburse Goldman, Sachs & Co. for carrying costs associated with such payment 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, except as provided in this Section, and Sections 9 and 12 hereof, the Underwriters will pay all of their own costs and expenses, including 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 and one half of the costs associated with any chartered aircraft used in connection with the roadshow.

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 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

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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) Ropes & Gray LLP, counsel for the Underwriters, shall have furnished to you such written opinion or opinions dated such Time of Delivery in form and substance satisfactory to you;

(c) (i) Latham & Watkins LLP, counsel for the Company, shall have furnished to you their written opinion, dated such Time of Delivery, in form and substance satisfactory to you and your counsel;

(ii) The respective counsel for each of the Selling Stockholders, as indicated in Schedule V hereto, each shall have furnished to you their written opinion with respect to each of the Selling Stockholders who are selling Shares at such Time of Delivery and for whom they are acting as counsel, dated such Time of Delivery in form and substance satisfactory to you and your counsel;

(iii) Wilmer Cutler Pickering Hale and Dorr LLP, counsel for Streetcar Limited, shall have furnished to you their written opinion, dated such Time of Delivery, in form and substance satisfactory to you and your counsel;

(d) 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, PricewaterhouseCoopers LLP and Baker Tilly Virchow Krause, LLP shall each have furnished to you a letter or letters, dated the respective dates of delivery thereof, in form and substance satisfactory to you, to the effect set forth in Annex I hereto (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(b) hereto);

(e) (i) Neither the Company nor any of its subsidiaries shall 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, otherwise than as set forth or contemplated in the Pricing Prospectus, and (ii) since the respective dates as of which information is given in the Pricing Prospectus there shall not have

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been any change in the capital stock (other than as a result of the exercise of stock options pursuant to the Company Incentive Plans or upon the exercise of warrants, or the conversion or exchange of convertible or exchangeable securities outstanding as of the date of this Agreement) or long-term debt of the Company or any of its subsidiaries 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, otherwise than as set forth or contemplated in the Pricing Prospectus, 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;

(f) On or after the Applicable Time (i) no downgrading shall have occurred in the rating accorded the Company’s debt securities by any “nationally recognized statistical rating organization”, as that term is defined by the Commission for purposes of Rule 436(g)(2) under the Act, and (ii) no such organization shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of any of the Company’s debt securities;

(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 New York Stock Exchange or on NASDAQ; (ii) a suspension or material limitation in trading in the Company’s securities on NASDAQ; (iii) a general moratorium on commercial banking activities declared by either Federal or New York State or the Commonwealth of Massachusetts 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 on NASDAQ; and

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

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Selling Stockholder, substantially to the effect set forth in Section 1(b)(iv) hereof in form and substance satisfactory to you;

(j) The Company shall have complied with the provisions of Section 5(c) hereof with respect to the furnishing of prospectuses on the 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 duly authorized representatives of the Selling Stockholders, respectively, 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 the Company shall have furnished or caused to be furnished to you certificates as to the matters set forth in subsections (a) and (e) of this Section and as to such other matters as you may reasonably request.

9. (a) The Company 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, 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 or the Independent Underwriter in connection with investigating or defending any such action or claim as such expenses are incurred; provided, however, that the Company 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 written information furnished to the Company by any Underwriter through the Representatives expressly for use therein. The Company also agrees to indemnify and hold harmless the Independent Underwriter and each person, if any, who controls the Independent Underwriter within the meaning of either Section 15 of the Act, or Section 20 of the Exchange Act, from and against any and all losses, claims, damages, liabilities and judgments incurred as a result of the Independent Underwriter’s participation as Independent Underwriter

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in connection with the offering of the Shares, except for any losses, claims, damages, liabilities, and judgments finally determined by a court of competent jurisdiction or any arbitration tribunal to have resulted from the Independent Underwriter’s, or such controlling person’s, gross negligence or willful misconduct, and to reimburse the Independent Underwriter for any legal or other expenses reasonably incurred by the Independent Underwriter in connection with investigating or defending any such action or claim as such expenses are incurred.

(b) Each of the Selling Stockholders, severally and not jointly, (i) 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 Selling Stockholder Information furnished to the Company by such Selling Stockholder expressly for use therein; (ii) will indemnify and hold harmless the Independent Underwriter and each person, if any, who controls the Independent Underwriter within the meaning of either Section 15 of the Act, or Section 20 of the Exchange Act, from and against any and all losses, claims, damages, liabilities and judgments incurred as a result of the Independent Underwriter’s participation as Independent Underwriter in connection with the offering of the Shares, except for any losses, claims, damages, liabilities, and judgments finally determined by a court of competent jurisdiction or any arbitration tribunal to have resulted from the Independent Underwriter’s, or such controlling person’s, gross negligence or willful misconduct; and provided further, that the provisions of Section 9(b)(ii) shall apply to the Selling Stockholder only after the Independent Underwriter shall have made a demand upon the Company to satisfy the obligations under this Section 9(a) and such demand remains unsatisfied for a period of 90 days or more; and (iii) and will reimburse each Underwriter and the Independent Underwriter for any legal or other expenses reasonably incurred by such Underwriter in connection with investigating or defending any such actions or claims as such expenses are incurred; provided, however, that such Selling Stockholder shall not be liable in any such case in Section 9(b)(i) to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue

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statement or alleged untrue statement or omission or alleged omission made in the Registration Statement, any Preliminary Prospectus or the Prospectus or any such amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use therein; and provided, further, that the liability of each of the Selling Stockholder pursuant to this subsection (b) shall not exceed the Net Proceeds (as defined below) received by such Selling Stockholder.

(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 written information furnished to the Company by such Underwriter through the Representatives 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 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

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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; provided, however that if indemnity may be sought pursuant to the second sentence of Section 9(a) or Section 9(b)(ii) above, then in addition to such separate counsel of the Underwriters, their affiliates and such control persons of the Underwriters, the indemnifying party shall be liable for fees and expenses of not more than one separate firm (in addition to any local counsel) for J.P. Morgan Securities LLC in its capacity as Independent Underwriter, its affiliates, directors, officers and all persons, if any, who control J.P. Morgan Securities LLC within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act. 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.

(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 each Selling Stockholder, respectively, on the one hand and the Underwriters or the Independent Underwriter in its capacity as a “qualified independent underwriter”, as the case may be, 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 each Selling Stockholder, respectively, on the one hand and the Underwriters or the Independent Underwriter in its capacity as a “qualified independent underwriter”, as the case may be, 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 such Selling Stockholder 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 (net of

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underwriting discounts and commissions but before deducting any other expenses) (the “Net Proceeds”) 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. Each of the Company, the Selling Stockholders and the Underwriters agrees that the Independent Underwriter will not receive any additional benefits hereunder for serving as the “qualified independent underwriter” in connection with the offering of the Shares. 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 the Selling Stockholders on the one hand or the Underwriters or the Independent Underwriter in its capacity as a “qualified independent underwriter”, as the case may be, 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), 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. Notwithstanding the provisions of this Section 9(e), no Selling Stockholder shall be required to contribute any amount, taken together with any amount paid or payable by such Selling Stockholder pursuant to Section 9(b), in excess of the aggregate Net Proceeds from the Shares sold by such Selling Stockholder under this Agreement. The Selling Stockholders’ obligations to contribute as provided in this Section 9(e) are several in proportion to the net proceeds received by them, respectively, from the sale of the shares of Stock under this Agreement and not joint.

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 (including any person who, with his or her consent, is named in the Registration Statement as about to become a director of the Company) and to each person, if any, who controls the Company or any Selling Stockholder within the meaning of the Act.

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 and 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 reasonable 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

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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.

(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 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 and the Selling Stockholders 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 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 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 except as provided in Sections 7 and 9 hereof.

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

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given by you jointly or by the Representatives on behalf of you as the representatives; 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.

All statements, requests, notices and agreements hereunder shall be in writing, and if to the Underwriters shall be delivered or sent by mail or facsimile transmission to you as the representatives in care of Goldman, Sachs & Co., 200 West Street, New York, New York 10282, Attention: Registration Department and J.P. Morgan Securities LLC 383 Madison Avenue, New York, New York 10179 (fax: (212)  ###-###-####), Attention: Equity Syndicate Desk, with a copy to the Legal Department; if to any Selling Stockholder, shall be delivered or sent by mail or facsimile transmission to counsel for such Selling Stockholder at its address set forth in Schedule V hereto; and if to the Company shall be delivered or sent by mail or facsimile transmission to the address of the Company set forth in the Registration Statement, Attention: Secretary, with a copy to Latham & Watkins LLP, John Hancock Tower, 200 Clarendon Street, Boston, MA, 02116, Attention: John Chory, Esq., facsimile (617)  ###-###-####; provided, however, that any notice to an Underwriter pursuant to Section 9(d) hereof shall be delivered or sent by mail or facsimile transmission to such Underwriter at its address set forth in its Underwriters’ 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) shall be in writing, and if to the Underwriters shall be delivered or sent by mail or facsimile transmission to you as the representatives at Goldman, Sachs & Co., 200 West Street, New York, New York 10282, Attention: Control Room and J.P. Morgan Securities LLC 383 Madison Avenue, New York, New York 10179 (fax: (212)  ###-###-####), Attention: Equity Syndicate Desk, with a copy to the Legal Department. 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.

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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, D.C. is open for business.

16. The Company and each of the Selling Stockholders 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, including the Independent Underwriter, is acting solely as a principal and not the agent or fiduciary of the Company or such Selling Stockholder, (iii) no Underwriter, including the Independent 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 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 have each consulted its own legal and financial advisors to the extent it deemed appropriate. The Company and each of the Selling Stockholders agree that they will not claim that the Underwriters (including the Independent Underwriter), or any of them, has rendered advisory services of any nature or respect, or owes a fiduciary or similar duty to the Company or the Selling Stockholders, in connection with such transaction or the process leading thereto.

17. This Agreement supersedes all prior agreements and understandings (whether written or oral) between 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 and each of the Selling Stockholders agree 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, each of the Selling Stockholders 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.

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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.

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.

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.

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On behalf of each of the Underwriters

SCHEDULE I

SCHEDULE II

Electronic road show

SCHEDULE III

(a) Materials Other Than the Pricing Prospectus that Comprise the Pricing Disclosure Package:

[None]

(b) Issuer Free Writing Prospectuses Not Included in the Pricing Disclosure Package:

Electronic road show

(c) Pricing Information:

Price to public: $            

Number of Shares to be sold by the Company:

Number of Shares to be sold by Selling Stockholders:

SCHEDULE IV

Persons Subject to the Lock-Up Period Pursuant to Lock-up Agreements

List of Directors, Officers, Selling Stockholders and holders of substantially all shares of Stock

[NAMES]

SCHEDULE V

The Selling Stockholders, as a group, are represented by Edwards Angell Palmer & Dodge LLP, 111 Huntington Avenue, Boston, MA 02199, except as provided below.

Each of the Selling Stockholders has appointed Scott W. Griffith, Edward G. Goldfinger and Dean Breda, as the Attorneys-in-Fact for such Selling Stockholder.

ANNEX I

Pursuant to Section 8(d) of the Underwriting Agreement, the accountants shall furnish letters to the Underwriters to the effect that:

(i) They are independent certified public accountants with respect to the Company and its subsidiaries within the meaning of the Act and the applicable published rules and regulations thereunder;

(ii) In their opinion, the financial statements and any supplementary financial information and schedules (and, if applicable, financial forecasts and/or pro forma financial information) examined by them and included in the Prospectus or the Registration Statement comply as to form in all material respects with the applicable accounting requirements of the Act and the related published rules and regulations thereunder; and, if applicable, they have made a review in accordance with standards established by the American Institute of Certified Public Accountants of the unaudited consolidated interim financial statements, selected financial data, pro forma financial information, financial forecasts and/or condensed financial statements derived from audited financial statements of the Company for the periods specified in such letter, as indicated in their reports thereon, copies of which have been separately furnished to the representatives of the Underwriters (the “Representatives”) and are attached hereto;

(iii) They have made a review in accordance with standards established by the American Institute of Certified Public Accountants of the unaudited condensed consolidated statements of income, consolidated balance sheets and consolidated statements of cash flows included in the Prospectus as indicated in their reports thereon copies of which have been separately furnished to the Representatives and are attached hereto and on the basis of specified procedures including inquiries of officials of the Company who have responsibility for financial and accounting matters regarding whether the unaudited condensed consolidated financial statements referred to in paragraph (vi)(A)(i) below comply as to form in all material respects with the applicable accounting requirements of the Act and the related published rules and regulations, nothing came to their attention that cause them to believe that the unaudited condensed consolidated financial statements do not comply as to form in all material respects with the applicable accounting requirements of the Act and the related published rules and regulations;

(iv) The unaudited selected financial information with respect to the consolidated results of operations and financial position of the Company for the five most recent fiscal years included in the Prospectus agrees with the corresponding amounts (after restatements where applicable) in the audited consolidated financial statements for such five fiscal years;

(v) They have compared the information in the Prospectus under selected captions with the disclosure requirements of Regulation S-K and on the basis of limited procedures specified in such letter nothing came to their attention as a result of the foregoing procedures that caused them to believe that this information does not conform in all material respects with the disclosure requirements of Items 301, 302, 402 and 503(d), respectively, of Regulation S-K;

(vi) On the basis of limited procedures, not constituting an examination in accordance with generally accepted auditing standards, consisting of a reading of the unaudited financial statements and other information referred to below, a reading of the latest available interim financial statements of the Company and its subsidiaries, inspection of the minute books of the Company and its subsidiaries since the date of the latest audited financial statements included in the Prospectus, inquiries of officials of the Company and its subsidiaries responsible for financial and accounting matters and such other inquiries and procedures as may be specified in such letter, nothing came to their attention that caused them to believe that:

(A) (i) the unaudited consolidated statements of income, consolidated balance sheets and consolidated statements of cash flows included in the Prospectus do not comply as to form in all material respects with the applicable accounting requirements of the Act and the related published rules and regulations, or (ii) any material modifications should be made to the unaudited condensed consolidated statements of income, consolidated balance sheets and consolidated statements of cash flows included in the Prospectus for them to be in conformity with generally accepted accounting principles;

(B) any other unaudited income statement data and balance sheet items included in the Prospectus do not agree with the corresponding items in the unaudited consolidated financial statements from which such data and items were derived, and any such unaudited data and items were not determined on a basis substantially consistent with the basis for the corresponding amounts in the audited consolidated financial statements included in the Prospectus;

(C) the unaudited financial statements which were not included in the Prospectus but from which were derived any unaudited condensed financial statements referred to in clause (A) and any unaudited income statement data and balance sheet items included in the Prospectus and referred to in clause (B) were not determined on a basis substantially consistent with the basis for the audited consolidated financial statements included in the Prospectus;

(D) any unaudited pro forma consolidated condensed financial statements included in the Prospectus do not comply as to form in all material respects with the applicable accounting requirements of the Act and the published rules and regulations thereunder or the pro forma adjustments have not been properly applied to the historical amounts in the compilation of those statements;

(E) as of a specified date not more than five days prior to the date of such letter, there have been any changes in the consolidated capital stock (other than issuances of capital stock upon exercise of options and stock appreciation rights, upon earn-outs of performance shares and upon conversions of convertible securities, in each case which were outstanding on the date of the latest financial statements included in the Prospectus) or any increase in the consolidated long-term debt of the Company and its subsidiaries, or any decreases in consolidated net current assets or stockholders’ equity or other items specified by the Representatives, or any increases in any items specified by the Representatives, in each case as compared with amounts shown in the latest balance sheet included in the Prospectus, except in each case for changes, increases or decreases which the Prospectus discloses have occurred or may occur or which are described in such letter; and

(F) for the period from the date of the latest financial statements included in the Prospectus to the specified date referred to in clause (E) there were any decreases in consolidated net revenues or operating profit or the total or per share amounts of consolidated net income or other items specified by the Representatives, or any increases in any items specified by the Representatives, in each case as compared with the comparable period of the preceding year and with any other period of corresponding length specified by the Representatives, except in each case for decreases or increases which the Prospectus discloses have occurred or may occur or which are described in such letter; and

(vii) In addition to the examination referred to in their report(s) included in the Prospectus and the limited procedures, inspection of minute books, inquiries and other procedures referred to in paragraphs (iii) and (vi) above, they have carried out certain specified procedures, not constituting an examination in accordance with generally accepted auditing standards, with respect to certain amounts, percentages and financial information specified by the Representatives, which are derived from the general accounting records of the Company and its subsidiaries, which appear in the Prospectus, or in Part II of, or in exhibits and schedules to, the Registration Statement specified by the Representatives, and have compared certain of such amounts, percentages and financial information with the accounting records of the Company and its subsidiaries and have found them to be in agreement.

EXHIBIT A

FORM OF LOCK-UP AGREEMENT