Underwriting Agreement

collectively called the “Optional Shares.”  The Firm Shares and the Optional Shares that the Underwriters may elect to purchase pursuant to Section 2 hereof are herein collectively called the “Shares.”

As part of the offering contemplated by this Agreement, Citigroup Global Markets Inc. has agreed to reserve, out of the Shares set forth opposite its name on the Schedule I hereto, up to [                   ] shares for sale to the Company’s employees, officers, and directors and other parties associated with the Company (collectively, the “Participants”), as set forth in the Prospectus under the heading “Underwriting” (the “Directed Share Program”). The Shares to be sold by Citigroup Global Markets Inc. pursuant to the Directed Share Program (the “Directed Shares”) will be sold by Citigroup Global Markets Inc. pursuant to this Agreement at the public offering price. Any Directed Shares not orally confirmed for purchase by any Participants by 9:00 A.M. New York City time on the business day following the date on which this Agreement is executed will be offered to the public by Citigroup Global Markets Inc. as set forth in the Prospectus.

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. 333-126280) (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 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, 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 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 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”; 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

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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 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 any statements or omissions made in reliance upon and in conformity with information furnished in writing to the Company by any Underwriter through the Representatives expressly for use therein;

(iii)           For the purposes of this Agreement, the “Applicable Time” is      :          m (New York City time) on the date of this Agreement; the Pricing Prospectus as supplemented by the Issuer Free Writing Prospectuses and other documents listed in Schedule III(a) hereto, (collectively, the “Pricing Disclosure Package”) taken together 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 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; if there occurs an event or development, as a result of which the Pricing Disclosure Package would contain an untrue statement of a material fact or would omit to state a material fact necessary in order to make the statements therein not misleading, in light of the circumstances in which they were made, the Company will promptly notify the Representatives; 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 any Underwriter through the Representatives expressly for use therein;

(iv)           The Registration Statement conforms and the Prospectus and any further amendments or supplements to the Registration Statement or the Prospectus will conform, in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder and do not and will not, as of the applicable effective date as to each part of the Registration Statement and any amendment thereto 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 any Underwriter through the Representatives expressly for use therein;

(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 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 each of the Pricing Prospectus and the 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 or long-term debt of the Company or any of its subsidiaries or any material adverse change, or

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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, otherwise than as set forth or contemplated in Registration Statement and 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 each of the Pricing Prospectus and the Prospectus or such as do not materially affect the value of such property and do not interfere with the use made and proposed to be made of such property by the Company and its subsidiaries; and except as could not reasonably be expected to have a material adverse effect upon the business, properties, financial condition or earnings of the Company and its subsidiaries taken as a whole (a “Material Adverse Effect”), any real property and buildings held under lease by the Company and its subsidiaries are held by them under valid, subsisting and enforceable leases;

(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, except where the failure to so qualify or be in good standing could not reasonably be expected to have a Material Adverse Effect; and each subsidiary of the Company has been duly incorporated or organized and is validly existing as a corporation, limited liability company or limited partnership, as applicable, in good standing under the laws of its jurisdiction of incorporation or organization;

(viii)         The Company has an authorized capitalization as set forth in each of the Pricing Prospectus and the Prospectus, and all of the issued shares of capital stock of the Company have been duly and validly authorized and issued, are fully paid and non-assessable; and all of the issued shares of capital stock of each subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and (except for directors’ qualifying shares and except as otherwise set forth in each of the Pricing Prospectus and the Prospectus) are owned directly or indirectly by the Company, free and clear of all liens, encumbrances, equities or claims;

(ix)            The Company Shares 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;

(x)             The Selling Stockholders Firm Shares and the Optional Shares have been duly and validly authorized and issued and are fully paid and non-assessable;

(xi)            This Agreement has been duly authorized, executed and delivered by the Company;

(xii)           Prior to the date hereof, neither the Company nor any of its affiliates has taken any action which is designed to or which has constituted or which might have been expected to cause or result in stabilization or manipulation of the price of any security of the Company in connection with the offering of the Shares;

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(xiii)          The issue and sale of the Shares to be sold by the Company and the compliance by the Company with all of the provisions of this Agreement and the consummation of the transactions herein contemplated will not, except as could not reasonably be expected to have a Material Adverse Effect, 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, nor will such action result in any violation of the provisions of the Certificate of Incorporation or By-laws of the Company or any of its subsidiaries or, except as could not reasonably be expected to have a Material Adverse Effect, any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties; and no consent, approval, authorization, order, registration or qualification of or with any such court or governmental agency or body is required for the issue and sale of the Shares or the consummation by the Company of the transactions contemplated by this Agreement, except for 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;

(xiv)         Neither the Company nor any of its subsidiaries is in violation of its Certificate of Incorporation or By-laws, or except as could not reasonably be expected to have a Material Adverse Effect, in default in the performance or observance of any material obligation, 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;

(xv)          The statements set forth in each of the Pricing Prospectus and the Prospectus under the caption “Description of Capital Stock”, insofar as they purport to constitute a summary of the terms of the Stock, under the captions “Certain U.S. Federal Income and Estate Tax Consequences to Non-U.S. Holders”, “Underwriting”, “Certain Relationships and Related Party Transactions” and under the caption “Description of Indebtedness,” insofar as they purport to describe the provisions of the laws and documents referred to therein, are accurate, complete and fair in all material respects;

(xvi)         Other than as set forth in each of the Pricing Prospectus and the 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 Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others;

(xvii)        Neither the Company nor its subsidiaries is and, after giving effect to the offering and sale of the Shares, none of them will be an “investment company”, as such term is defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”);

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

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(xix)          Deloitte & Touche LLP, who have certified certain financial statements of the Company and its subsidiaries, and PricewaterhouseCoopers LLP, who have also certified certain financial statements of the Company and its subsidiaries, are each independent public accountants as required by the Act and the rules and regulations of the Commission thereunder;

(xx)           The Company maintains a system of internal control over financial reporting (as such term is defined in Rule 13a-15(f) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) sufficient to provide reasonable assurances that (A) transactions are executed in accordance with management’s general or specific authorization, (B) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain accountability for assets, (C) access to assets is permitted only in accordance with management’s general or specific authorization and (D) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences; except as disclosed in each of the Pricing Prospectus and the Prospectus, 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;

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

(xxii)         The Company maintains disclosure controls and procedures (as such term is defined in Rule 13a-15(e) of the Exchange Act) designed to ensure that information required to be disclosed by the reports that it files or submits under the Exchange Act are recorded, processed, summarized and reported in accordance with the Exchange Act and the rules and regulations thereunder; and the Company has carried out evaluations, under the supervision and with the participation of its management, of the effectiveness of the design and operation of the Company’s disclosure controls and procedures in accordance with Rule 13a-15 of the Exchange Act;

(xxiii)        The Company and each of its subsidiaries has complied in all respects with all laws, regulations and orders applicable to it or its businesses, the violation of which would have a Material Adverse Effect;

(xxiv)        (A) No labor disturbance by the employees of the Company or any of its subsidiaries exist or, to the knowledge of the Company and its subsidiaries, is imminent; and (B)  there are no unfair labor practice complaints pending against the Company or any of its subsidiaries or, to the knowledge of the Company and its subsidiaries, is threatened against any of them, which, in the case of either (A) or (B), would result in a Material Adverse Effect; and

(xxv)         The Company and each of its subsidiaries owns or possesses or has the right to use the patents, patent rights, licenses, inventions, copyrights, know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), trademarks, service marks and trade names (collectively, the “Intellectual Property”) presently employed by it in connection with, and material to, collectively or in the aggregate, the operation of the businesses now operated by it, and, except as described in the Prospectus, neither the Company nor its subsidiaries has received any notice

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of infringement of or conflict with asserted rights of others with respect to the foregoing which, individually or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would result in a Material Adverse Effect.

Furthermore, the Company represents and warrants to Citigroup Global Markets Inc. that (i) the Registration Statement, the Pricing Prospectus, the Prospectus and any Issuer Free Writing Prospectus comply, and any further amendments or supplements thereto will comply, with any applicable laws or regulations of foreign jurisdictions in which the Pricing Prospectus, the Prospectus or any Issuer Free Writing Prospectus, as amended or supplemented, if applicable, are distributed in connection with the Directed Share Program, and (ii) no authorization, approval, consent, license, order, registration or qualification of or with any government, governmental instrumentality or court, other than such as have been obtained, is necessary under the securities laws and regulations of foreign jurisdictions in which the Directed Shares are offered outside the United States. The Company has not offered, or caused the Underwriters to offer, Shares to any person pursuant to the Directed Share Program with the specific intent to unlawfully influence (i) a customer or supplier of the Company to alter the customer’s or supplier’s level or type of business with the Company, or (ii) a trade journalist or publication to write or publish favorable information about the Company or its products.

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

(i)             All consents, approvals, authorizations and orders necessary for the execution and delivery by such Selling Stockholder of this Agreement and the Power of Attorney and the Custody Agreement hereinafter referred to, and for the sale and delivery of the Shares to be sold by such Selling Stockholder hereunder, have been obtained; and such Selling Stockholder has full right, power and authority to enter into this Agreement, the Power of Attorney and the Custody Agreement and to sell, assign, transfer and deliver the Shares to be sold by such Selling Stockholder hereunder;

(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 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, nor will such action 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, the Limited Liability Company Agreement of such Selling Stockholder if such Selling Stockholder is a limited liability company and the Partnership Agreement of such Selling Stockholder if such Selling Stockholder is a partnership or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over such Selling Stockholder or the property of such Selling Stockholder;

(iii)           Such Selling Stockholder has, and immediately prior to each Time of Delivery (as defined in Section 4(a) hereof) such Selling Stockholder will have, good and valid title to the Shares to be sold by such Selling Stockholder hereunder, free and clear of all liens, encumbrances, equities or claims; and, upon delivery of such Shares and payment therefor

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pursuant hereto, good and valid title to such Shares, free and clear of all liens, encumbrances, equities or claims, will pass to the several Underwriters;

(iv)           Each of the Selling Stockholders has executed and delivered to the Representatives a lock-up agreement (the “Lock-Up Agreement”), pursuant to which each Selling Stockholder has agreed during the period beginning from the date hereof and continuing to and including the date 180 days after the date of the Prospectus (the initial “Lock-Up Period”), not to offer, sell, hedge or otherwise dispose of, except as provided in the Lock-Up Agreement, any securities of the Company that are substantially similar to the Shares, including but not limited to any securities that are convertible into or exchangeable for, or that represent the right to receive, Stock or any such substantially similar securities (other than pursuant to employee stock option plans existing on, or upon the conversion or exchange of convertible or exchangeable securities outstanding as of, the date of this Agreement), without the prior written consent of Citigroup Global Markets Inc.; 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 16-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 Citigroup Global Markets Inc. waives, in writing, such extension; such Selling Stockholder hereby acknowledges that the Company has agreed herein to provide written notice of any event that would result in an extension of the Lock-Up Period pursuant to the previous sentence to such Selling Stockholder (in accordance with Section 13 herein) and agrees that any such notice properly delivered will be deemed to have been given to, and received by, the Selling Stockholder; such Selling Stockholder hereby further agrees that, prior to engaging in any transaction or taking any other action that is subject to the terms of this provision during the period from the date hereof to and including the 34th day following the expiration of the initial Lock-Up Period, it will give notice thereof to the Company and will not consummate such transaction or take any such action unless it has received written confirmation from the Company that the Lock-Up Period (as such may have been extended pursuant to the previous paragraph) has expired.

(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 might 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 that any statements or omissions made in the Registration Statement, the Pricing Prospectus, the Prospectus, any Issuer Free Writing Prospectus or any amendment or supplement thereto are made in reliance upon and in conformity with written information relating to the Selling Stockholder furnished to the Company by such Selling Stockholder expressly for use therein, such Registration Statement, Pricing Prospectus, Prospectus, Issuer Free Writing Prospectus and any further amendments or supplements thereto, as the case may be, did and will, conform in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder and will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading;

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(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 properly completed and executed United States Treasury Department Form W-9 (if such Selling Stockholder is a United States person, as defined under Section 7701(a)(30) of the Internal Revenue Code of 1986, as amended) or Form W-8 (if such Selling Stockholder is not a United States person, as defined under Section 7701(a)(30) under the Internal Revenue Code of 1986, as amended) (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 Kenneth L. Walker and James B. Hirshorn, as custodian (the “Custodian”), and such Selling Stockholder has duly executed and delivered a Power of Attorney, in the form heretofore furnished to you (the “Power of Attorney”), appointing the persons indicated in Schedule II hereto, and each of them, as such Selling Stockholder’s attorneys-in-fact (the “Attorneys-in-Fact”) with authority to execute and deliver this Agreement on behalf of such Selling Stockholder, to determine the purchase price to be paid by the Underwriters to the Selling Stockholders as provided in Section 2 hereof, to authorize the delivery of the Shares to be sold by such Selling Stockholder hereunder and otherwise to act on behalf of such Selling Stockholder in connection with the transactions contemplated by this Agreement and the Custody Agreement; 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; 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, limited liability company or corporation, by the dissolution of such partnership, limited liability company 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, limited liability company 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, (a) the Company and each of the Selling Stockholders agree, severally and not jointly, to sell to each of the Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company and each of the Selling Stockholders, at a purchase price per share of $[             ], the number of Firm Shares (to be

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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 II hereto by a fraction, the numerator of which is the aggregate number of Firm Shares to be purchased by such Underwriter as set forth opposite the name of such Underwriter in Schedule I hereto and the denominator of which is the aggregate number of Firm Shares to be purchased by all of the Underwriters from the Company and all of the Selling Stockholders hereunder and (b) in the event and to the extent that the Underwriters shall exercise the election to purchase Optional Shares as provided below, 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 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 Selling Stockholders, as and to the extent indicated in Schedule II 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 each Selling Stockholder as set forth in Schedule II hereto. Any such election to purchase Optional Shares may be exercised only by written notice from you to 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 defined in Section 4(a) hereof) or, unless you 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