UNDERWRITING AGREEMENT

Exhibit 1

UNDERWRITING AGREEMENT

United States Steel Corporation

$750,000,000 4.00% Senior Convertible Notes due 2014

April 28, 2009

J.P. Morgan Securities Inc.

Morgan Stanley & Co. Incorporated

As Representatives of the

several Underwriters listed

in Schedule 1 hereto

c/o J.P. Morgan Securities Inc.

383 Madison Avenue

New York, New York 10179

c/o Morgan Stanley & Co. Incorporated

1585 Broadway

New York, New York 10036

Ladies and Gentlemen:

United States Steel Corporation, a Delaware corporation (the “Company”), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), $750,000,000 principal amount of its 4.00% Senior Convertible Notes due 2014 (the “Underwritten Securities”) and, at the option of the Underwriters, up to an additional $112,500,000 principal amount of 4.00% Senior Convertible Notes due 2014 (the “Option Securities”). The Underwritten Securities and the Option Securities are herein referred to as the Securities. The Securities will be convertible into shares (the “Underlying Securities”) of Common Stock, par value $1.00 per share (the “Common Stock”), of the Company. The Securities will be issued pursuant to an indenture dated as of May 21, 2007 (the “Base Indenture”) between the Company and The Bank of New York Mellon, as trustee (the “Trustee”), as heretofore supplemented and amended and as to be further supplemented and amended by a Third Supplemental Indenture, dated on or about May 4, 2009, to the Base Indenture relating to the Securities (the “Supplemental Indenture” and, together with the Base Indenture and any other amendments or supplements thereto, the “Indenture”), between the Company and the Trustee.

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The Company hereby confirms its agreement with the several Underwriters concerning the purchase and sale of the Securities, as follows:

1. Registration Statement . The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement on Form S-3 (No. 333-141080), including a prospectus (the “Basic Prospectus”), relating to the Securities. The Company has also filed, or proposes to file, with the Commission pursuant to Rule 424 under the Securities Act a prospectus supplement specifically relating to the Securities (the “Prospectus Supplement”). The registration statement, as amended at the time of this Agreement, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness, is referred to herein as the “Registration Statement”; and as used herein, the term “Prospectus” means the Basic Prospectus included in the Registration Statement (and any amendments thereto) as supplemented by the prospectus supplement specifically relating to the Securities in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Securities and the term “Preliminary Prospectus” means the preliminary prospectus supplement specifically relating to the Securities together with the Basic Prospectus. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus. References herein to the Registration Statement, the Basic Prospectus, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein. The terms “supplement,” “amendment” and “amend” as used herein with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed by the Company under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (the “Exchange Act”) subsequent to the date of this Agreement which are deemed to be incorporated by reference therein. For purposes of this Agreement, the term “Effective Time” means the effective date of the Registration Statement with respect to the offering of the Securities, as determined for the Company pursuant to Section 11 of the Securities Act and Item 512 of Regulation S-K, as applicable.

At or prior to the time when the first sale of the Securities is made (the “Time of Sale”), the Company will prepare certain information (collectively, the “Time of Sale Information”), which includes a Preliminary Prospectus, dated April 27, 2009, and each “free writing prospectus” (as defined pursuant to Rule 405 of the Securities Act) identified in Schedule 2 hereto.

2. Purchase of the Securities by the Underwriters . (a) The Company agrees to issue and sell the Securities to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective principal amount of the Securities set forth opposite such Underwriter’s name in Schedule 1 hereto at a price equal to 97.00% of the principal amount thereof plus accrued interest, if any, from May 4, 2009, to the Closing Date (as such term is hereinafter defined). The Company will not be obligated to deliver any of the Securities except upon payment for all the Securities to be purchased as provided herein.

In addition, in reliance upon the representations, warranties and agreements herein contained and subject to the terms and conditions herein set forth, the Company hereby grants an option to the several Underwriters to purchase, severally and not jointly, the Option Securities. The option granted hereby will expire 30 days after the date of the Prospectus Supplement and

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may be exercised in whole or in part from time to time upon written notice (each, an “Option Exercise Notice”) from the Representatives setting forth the number of Option Securities as to which the several Underwriters are then exercising the option and the time and date of payment and delivery for such Option Securities. The number of Option Securities to be purchased by each Underwriter shall be the same percentage of the total number of the Option Securities to be purchased by the several Underwriters as such Underwriter is purchasing of the Underwritten Securities. Any Additional Closing Date (as defined below) shall be determined by the Representatives, but shall not be later than five full business days after the date of the Option Exercise Notice unless otherwise agreed in writing by the parties hereto, nor in any event prior to the Closing Date. Any Option Exercise Notice shall be given at least two business days prior to the date and time of delivery specified therein.

(b) The Company understands that the Underwriters intend to make a public offering of the Securities as soon after the effectiveness of this Agreement as in the judgment of the Representatives is advisable, and initially to offer the Securities on the terms set forth in the Prospectus. The Company acknowledges and agrees that the Underwriters may offer and sell Securities to or through any affiliate of an Underwriter and that any such affiliate may offer and sell Securities purchased by it to or through any Underwriter.

(c) Payment for and delivery of the Securities will be made at the offices of Simpson Thacher & Bartlett LLP at 10:00 a.m., New York City time, on May 4, 2009, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representatives and the Company may agree upon in writing or, in the case of the Option Securities, on the date and at the time and place specified in the Option Exercise Notice. The time and date of such payment and delivery of the Underwritten Securities is referred to herein as the “Closing Date”, and the time and date of such payment and delivery for the Option Securities, if other than the Closing Date, is herein referred to as the “Additional Closing Date”.

(d) Payment for the Securities shall be made by wire transfer in immediately available funds to the account(s) specified by the Company to the Representatives against delivery to the nominee of The Depository Trust Company, for the account of the Underwriters, of one or more global notes representing the Securities (the “Global Notes”), with any transfer taxes payable in connection with the sale of the Securities duly paid by the Company. The Global Notes will be in form and substance reasonably satisfactory to the Representatives.

(e) The Company acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to any offering of the Securities contemplated hereby (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person with respect to any such offering. Additionally, no such Underwriter is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company shall consult with its own advisors concerning such matters and shall be responsible for making its own independent investigation and appraisal of the transactions contemplated hereby, and such Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by such Underwriters of the Company, the transactions contemplated thereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

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(f) The Company hereby confirms its engagement of Goldman, Sachs & Co. as, and Goldman, Sachs & Co. hereby confirms its agreement with the Company to render services as, a “qualified independent underwriter” within the meaning of Rule 2720(b)(15) of the National Association of Securities Dealers, Inc. (the “NASD”) with respect to the offering and sale of the Securities. Goldman, Sachs & Co., in its capacity as qualified independent underwriter and not otherwise, is referred to herein as the “QIU”. As compensation for the services of the QIU hereunder, the Company agrees to pay the QIU $10,000 on the Closing Date.

3. Representations and Warranties of the Company . The Company represents and warrants to each Underwriter that:

(a) Registration Statement and Prospectus. The Registration Statement has become effective under the Securities Act. The Registration Statement is an “automatic shelf registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date hereof; and no notice of objection of the Commission to the use of such registration statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company. The Company has not received any order suspending the effectiveness of the Registration Statement by the Commission and has not received notice of any proceeding for that purpose or notice of any action instituted pursuant to Section 8A of the Securities Act against the Company or related to the offering has been initiated or threatened by the Commission; as of the Effective Time, the Registration Statement complied, and as of the date of any amendment thereto will comply, in all material respects with the Trust Indenture Act of 1939, as amended, and the rules and regulations of the Commission thereunder (collectively the “Trust Indenture Act”) and the Securities Act and did not and will not contain any 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 not misleading; and as of the date of the Prospectus and any amendment or supplement thereto, the Prospectus did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus will not contain any 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 that the Company makes no representation and warranty with respect to (i) that part of the Registration Statement that constitutes the Statement of Eligibility and Qualification (Form T-1) of the Trustee under the Trust Indenture Act or (ii) any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto.

(b) Time of Sale Information. The Time of Sale Information, at the Time of Sale did not, and at the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating

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to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in such Time of Sale Information. No statement of material fact included in the Prospectus that is required to be included in the Time of Sale Information has been omitted from the Time of Sale Information and no statement of material fact included in the Time of Sale Information that is required to be included in the Prospectus has been omitted therefrom.

(c) Issuer Free Writing Prospectus. The Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not prepared, made, used, authorized, approved or referred to and will not prepare, make, use, authorize, approve or refer to any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Securities (each such communication by the Company or its agents and representatives (other than a communication referred to in clauses (i), (ii) and (iii) of this Section 3(c)), an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act, (ii) the Preliminary Prospectus, (iii) the Prospectus, (iv) the documents listed on Schedule 2 hereto and (v) any electronic road show or any other written communications, in each case approved in writing in advance by the Representatives. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act, has been or will be (within the time period specified in Rule 433) filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with the Preliminary Prospectus accompanying, or delivered prior to delivery of, or filed prior to the first use of such Issuer Free Writing Prospectus, did not, and at the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in any Issuer Free Writing Prospectus.

(d) Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, when filed with the Commission, conformed or will conform, as the case may be, in all material respects with the requirements of the Exchange Act and did not and will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(e) Company Organization and Good Standing. The Company has been duly incorporated and is an existing 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 Time of Sale Information and the Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so qualify would not reasonably be expected to have a material adverse effect upon the financial condition, business, properties or results of operations of the Company and its subsidiaries, taken as a whole (a “Material Adverse Effect”).

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(f) Subsidiary Organization and Good Standing. Each subsidiary of the Company listed on Annex A (each, a “Designated Subsidiary”) has been duly incorporated or otherwise organized and is an existing corporation, limited liability company or other business entity in good standing under the laws of the jurisdiction of its incorporation or organization, with power and authority (corporate, limited liability company and other) to own its properties and conduct its business as described in the Time of Sale Information and the Prospectus; and each Designated Subsidiary of the Company is duly qualified to do business as a foreign corporation or other business entity in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so qualify would not reasonably be expected to have a Material Adverse Effect; all of the issued and outstanding capital stock or other equity securities of each Designated Subsidiary of the Company have been duly authorized and are validly issued, fully paid and nonassessable; and the shares of capital stock or other equity securities of each Designated Subsidiary owned by the Company, directly or through subsidiaries, are owned free from liens, encumbrances and defects, except such liens, encumbrances and defects that would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. The entities listed on Annex A hereto include every subsidiary of the Company that is a “significant subsidiary” (as such term is defined in Rule 1-02 of Regulation S-X) of the Company.

(g) Capitalization. All outstanding shares of capital stock of the Company have been duly authorized and are validly issued, fully paid and non-assessable and are not subject to any pre-emptive or similar rights. The Company has an authorized capitalization as of March 31, 2009 as set forth in the Registration Statement, the Time of Sale Information and the Prospectus under the heading “Capitalization.” Except as described in or expressly contemplated by the Time of Sale Information and the Prospectus, there are no outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained in the Registration Statement, the Time of Sale Information and the Prospectus.

(h) No Broker’s Fees. Except as disclosed in the Time of Sale Information and the Prospectus, there are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with this offering.

(i) No Registration Rights. 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 Securities 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 with any securities being registered pursuant to any other registration statement filed by the Company under the Securities Act.

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(j) No Consents Required. No consent, approval, authorization, or order of, or filing with, any governmental agency or body or any court is required for the consummation of the transactions contemplated by this Agreement, the Securities and the Indenture (collectively, the “Transaction Documents”) in connection with the issuance and sale of the Securities (including the issuance of the Underlying Securities upon conversion thereof) or the consummation of the Transactions by the Company, except such (i) as have been obtained and made under the Securities Act and (ii) as may be required under state securities laws in connection with the purchase and distribution of the Securities by the Underwriters, and except for such consents, approvals, authorizations, orders or filings the failure of which to obtain or make would not reasonably be expected to have a Material Adverse Effect.

(k) No Conflicts. The execution, delivery and performance by the Company of the Transaction Documents, the issuance and sale of the Securities (including the issuance of the Underlying Securities upon conversion thereof) and compliance by the Company with the terms thereof and the consummation of the transactions contemplated by the Transaction Documents, will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, (i) any statute, any rule, regulation or order of any governmental agency or body or any court, domestic or foreign, having jurisdiction over the Company or any Designated Subsidiary of the Company or any of their properties, (ii) any agreement or instrument to which the Company or any such Designated Subsidiary is a party or by which the Company or any such Designated Subsidiary is bound or to which any of the properties of the Company or any such Designated Subsidiary is subject or (iii) the charter or by-laws of the Company or any such Designated Subsidiary.

(l) Due Authorization. The Company has full right, power and authority to execute and deliver the Transaction Documents and to perform its obligations hereunder and thereunder; and all action required to be taken for the due and proper authorization, execution and delivery of each of the Transaction Documents and the consummation of the transactions contemplated thereby has been duly and validly taken.

(m) The Indenture. The Indenture has been duly authorized by the Company and has been duly qualified under the Trust Indenture Act and the Base Indenture constitutes, and the Supplemental Indenture, when duly executed and delivered in accordance with its terms by each of the parties thereto, will constitute, a valid and legally binding agreement of the Company enforceable against the Company in accordance with its terms, except as enforceability may be limited by applicable bankruptcy, insolvency or similar laws affecting the enforcement of creditors’ rights generally or by equitable principles relating to enforceability (collectively, the “Enforceability Exceptions”).

(n) The Securities . The Securities have been duly authorized by the Company and, when duly executed, authenticated, issued and delivered in accordance with the Indenture and paid for as provided herein, will be duly and validly issued and outstanding and will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms, subject to the Enforceability Exceptions, and will be entitled to the benefits of the Indenture.

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(o) Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(p) No Violation or Default. Neither the Company nor any of the Designated Subsidiaries is (i) in violation of its respective charter or by-laws or other organizational documents, (ii) in default in the performance of any obligation, agreement, covenant or condition contained in any indenture, loan agreement, mortgage, lease or other agreement or instrument that is material to the Company and its subsidiaries, taken as a whole, to which the Company or any Designated Subsidiaries is a party or by which the Company or any Designated Subsidiaries or their respective property is bound, or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except for such defaults and violations in the case of these clauses (ii) and (iii) that would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(q) Title to Real and Personal Property. Except as disclosed in the Time of Sale Information and the Prospectus, the Company and the Designated Subsidiaries have good and marketable title to all real properties and all other properties and assets owned by them, in each case free from liens, encumbrances and defects, except such liens, encumbrances and defects that would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and except as disclosed in the Time of Sale Information and the Prospectus, the Company and its subsidiaries hold any leased real or personal property under valid and enforceable leases with no exceptions that would materially interfere with the business of the Company and its subsidiaries, taken as a whole. The Company and its subsidiaries own or lease all properties and assets necessary to conduct their business as described in the Time of Sale Information and the Prospectus.

(r) Licenses and Permits. The Company and the Designated Subsidiaries possess adequate certificates, authorities or permits issued by appropriate governmental agencies or bodies necessary to conduct their business as described in the Time of Sale Information and the Prospectus and have not received any notice of proceedings relating to the revocation or modification of any such certificate, authority or permit that, if determined adversely to the Company or any Designated Subsidiary, would reasonably be expected to have a Material Adverse Effect.

(s) Descriptions of the Transaction Documents. The Transaction Documents conform in all material respects to the descriptions thereof contained in the Time of Sale Information and the Prospectus.

(t) No Labor Disputes. Except as disclosed in the Registration Statement or the Prospectus, no labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent that would reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(u) Title to Intellectual Property. The Company and the Designated Subsidiaries own, possess or can acquire on reasonable terms, adequate trademarks, trade names and other rights to inventions, know-how, patents, copyrights, confidential information and other intellectual property (collectively, “intellectual property rights”) necessary to conduct its

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business as described in the Time of Sale Information and the Prospectus, or presently employed by them, and have not received any notice of infringement of or conflict with asserted rights of others with respect to any intellectual property rights that, if determined adversely to the Company or any of its Designated Subsidiaries, would reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(v) Compliance With Environmental Laws. Except as disclosed in the Time of Sale Information and the Prospectus, neither the Company nor any of its subsidiaries is in violation of any statute, any rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “environmental laws”), owns or operates any real property contaminated with any substance that is subject to any environmental laws, is liable for any off-site disposal or contamination pursuant to any environmental laws, or is subject to any claim relating to any environmental laws, which violation, contamination, liability or claim could reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect; and the Company is not aware of any pending investigation which would reasonably be expected to lead to such a claim.

(w) Legal Proceedings. Except as described in the Time of Sale Information and the Prospectus, there are no pending actions, suits or proceedings against or affecting the Company, any of its subsidiaries or any of their respective properties that, individually or in the aggregate would reasonably be expected to have a Material Adverse Effect, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement, or which are otherwise material in the context of the sale of the Securities; and, to the Company’s knowledge, no such actions, suits or proceedings are threatened.

(x) Financial Statements of the Company. The financial statements of the Company and the related notes thereto included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus present fairly the financial position of the Company and its consolidated subsidiaries as of the dates shown and their results of operations and cash flows for the periods shown, and, except as otherwise disclosed in the Time of Sale Information and the Prospectus, such financial statements have been prepared in conformity with the generally accepted accounting principles in the United States applied on a consistent basis throughout the periods covered thereby, and the supporting schedules included in the Registration Statement present fairly the information required to be stated therein; and the other financial information of the Company included in the Registration Statement, the Time of Sale Information and the Prospectus has been derived from the accounting records of the Company and its subsidiaries and presents fairly the information shown thereby.

(y) Taxes. The Company and its Designated Subsidiaries have timely filed all material federal, state, local and foreign income tax returns that have been required to be filed and have paid all taxes indicated by said returns and all assessments received by any of them to the extent that such material taxes have become due and are not being contested in good faith in appropriate proceedings. All material tax liabilities have been adequately provided for in the financial statements of the Company.

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(z) No Material Adverse Change. Since the date of the most recent financial statements of the Company included in the Registration Statement, the Time of Sale Information and the Prospectus, (i) there has not been any change in the capital stock or long term debt of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development involving a prospective material adverse change, in or affecting the business, properties, management, financial position, results of operations or prospects of the Company and its subsidiaries taken as a whole; (ii) neither the Company nor any of its subsidiaries has entered into any transaction or agreement that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole; and (iii) neither the Company nor any of its subsidiaries has sustained any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority, except in each case of (i), (ii) and (iii) of this Section 3(z) as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus.

(aa) Reporting Requirements. The Company is subject to the reporting requirements of either Section 13 or Section 15(d) of the Exchange Act and files reports with the Commission on the Electronic Data Gathering, Analysis, and Retrieval (EDGAR) system.

(bb) Independent Accountants. PricewaterhouseCoopers LLP, which has audited certain financial statements of the Company and its subsidiaries, is an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Company Accounting Oversight Board (United States) and as required by the Securities Act.

(cc) No Undisclosed Relationships. No relationship, direct or indirect, exists between or among the Company or any of its subsidiaries, on the one hand, and the directors, officers, stockholders, customers or suppliers of the Company or any of its subsidiaries, on the other, that is required by the Securities Act to be described in the Registration Statement, the Time of Sale Information and the Prospectus and that is not so described.

(dd) Compliance With ERISA. Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company or any of its affiliates for employees or former employees of the Company and its affiliates has been maintained in compliance in all material respects with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Internal Revenue Code of 1986, as amended (the “Code”); no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any such plan excluding transactions effected pursuant to a statutory or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “accumulated funding deficiency” as defined in Section 412 of the Code has been incurred, whether or not waived, and, except as otherwise disclosed in the Time of Sale Information and the Prospectus, the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued

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under such plan determined based on actuarial assumptions and methods that are compliant with the requirements of Code Section 430(h) and regulations thereunder; and neither the Company nor any of its affiliates has incurred, or reasonably expects to incur, any liability under Title IV of ERISA in respect of any Plan “or multiemployer plan” within the meaning of Section 4001(a)(3) of ERISA, other than liability for the payment of required PBGC insurance premiums under Section 4007 of ERISA.

(ee) Disclosure Controls. The Company and its subsidiaries maintain an effective system of “disclosure controls and procedures” (as defined in Rule 13a-15(e) of the Exchange Act) that is designed to ensure that information required to be disclosed by the Company in reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including controls and procedures designed to ensure that such information is accumulated and communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure. As of the date of the Time of Sale Information and the Prospectus, the Company and its subsidiaries have carried out evaluations of the effectiveness of their disclosure controls and procedures as required by Rule 13a-15 of the Exchange Act.

(ff) Accounting Controls. The Company and its subsidiaries maintain systems of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of their respective principal executive and principal financial officers, or persons performing similar functions, 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, including, but not limited to internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) 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 the Registration Statement, the Time of Sale Information and the Prospectus, there are no material weaknesses in the Company’s internal controls over financial reporting.

(gg) Sarbanes-Oxley Act. There is and has been no failure on the part of the Company or to the Company’s knowledge, any of the Company’s directors or officers, in their capacities as such, to comply in all material respects with any provision of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith, including Section 402 related to loans and Sections 302 and 906 related to certifications.

(hh) No Unlawful Payments. Neither the Company nor any of its subsidiaries nor, to the best knowledge of the Company, any director, officer, agent, employee or other person associated with or acting on behalf of the Company or any of its subsidiaries has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; (iii) violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977; or (iv) made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment.

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

(jj) Compliance with OFAC. None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Department of the Treasury (“OFAC”); and the Company will not, directly or indirectly, knowingly use the proceeds of the offering of the Securities hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(kk) No Stabilization. The Company has not taken, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Securities.

(ll) Investment Company Act. The Company is not and, after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Time of Sale Information and the Prospectus, will not be an “investment company” as defined in the Investment Company Act of 1940.

(mm) Status under the Securities Act. The Company is not an ineligible issuer and is a well-known seasoned issuer, in each case as defined under the Securities Act, in each case at the times specified in the Securities Act in connection with the offering of the Securities.

(nn) Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included in the Registration Statement, the Time of Sale Information and the Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(oo) Forward-Looking Statements. No forward-looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) contained in the Registration Statement, the Time of Sale Information or the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(pp) Underlying Securities. Upon issuance and delivery of the Securities in accordance with this Agreement and the Indenture, the Securities will be convertible at the option of the

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holder thereof into shares of Common Stock in accordance with the terms of the Securities and the Indenture. The Underlying Securities reserved for issuance upon conversion of the Securities have been duly authorized and reserved, and when issued upon such conversion of the Securities in accordance with the terms of the Securities, will be duly and validly issued, fully paid and non-assessable, and will conform in all material respects to the description thereof contained in the Time of Sale Information and the Prospectus; and the issuance of the Underlying Securities will not be subject to any preemptive or similar rights.

4. Further Agreements of the Company . The Company covenants and agrees with each Underwriter that:

(a) Filings with the Commission. The Company will (i) pay the registration fees for this offering within the time period required by Rule 456(b)1(i) under the Securities Act (without giving effect to the proviso therein) and in any event prior to the Closing Date and (ii) file the Prospectus in a form approved by the Underwriters with the Commission pursuant to Rule 424 under the Securities Act not later than the close of business on the second business day following the date of determination of the public offering price of the Securities or, if applicable, such earlier time as may be required by Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act. The Company will file any Issuer Free Writing Prospectus (including the Pricing Term Sheet substantially in the form of Schedule 3 hereto) to the extent required by Rule 433 under the Securities Act, and the Company will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, on the business day next succeeding the date of this Agreement in such quantities as the Representatives may reasonably request.

(b) Delivery of Copies. The Company will deliver, without charge, to each Underwriter (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and (B) during the Prospectus Delivery Period (as hereinafter defined), as many copies of the Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein) and each Issuer Free Writing Prospectus (if applicable) as the Representatives may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Securities as in the opinion of counsel for the Underwriters a prospectus relating to the Securities is required by law to be delivered (or would be required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Securities by any Underwriter or dealer.

(c) Amendments or Supplements; Issuer Free Writing Prospectuses . In connection with the transactions contemplated by the Agreement, before making, preparing, using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement or the Prospectus, the Company will furnish to the Representatives and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not make, prepare, use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus or file any such proposed amendment or supplement to which the Representatives reasonably object.

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(d) Notice to the Representatives. The Company will advise the Representatives promptly, and confirm such advice in writing, (i) when any amendment to the Registration Statement has been filed or becomes effective; (ii) when any supplement to the Prospectus, any amendment to the Prospectus or any Issuer Free Writing Prospectus has been filed; (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (iv) upon receipt of notice of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus or the Prospectus or the initiation or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (v) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, the Time of Sale Information or any Issuer Free Writing Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus, the Time of Sale Information or any Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; (vi) of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act; and (vii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Securities for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and the Company will use all reasonable efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus or the Prospectus or suspending any such qualification of the Securities and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

(e) Time of Sale Information. If at any time prior to the Closing Date (i) any event shall occur or condition shall exist as a result of which the Time of Sale Information as then amended or supplemented would 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, not misleading or (ii) it is necessary to amend or supplement the Time of Sale Information to comply with applicable law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) of this Section 4, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representatives may designate, such amendments or supplements to the Time of Sale Information as may be necessary so that the statements in the Time of Sale Information as so amended or supplemented will not, in the light of the circumstances, be misleading or so that the Time of Sale Information will comply with applicable law.

(f) Ongoing Compliance. If during the Prospectus Delivery Period (i) any event shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would 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 existing when the Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with applicable law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) of this Section 4, file with the Commission and furnish to the Underwriters and to such dealers as the

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Representatives may designate, such amendments or supplements to the Prospectus as may be necessary so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with applicable law.

(g) Blue Sky Compliance. The Company will qualify the Securities for offer and sale under the securities or Blue Sky laws of such U.S. jurisdictions as the Representatives shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Securities; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(h) Earning Statement. The Company will make generally available to its security holders and the Representatives as soon as practicable an earning statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the “effective date” (as defined in Rule 158) of the Registration Statement.

(i) Use of Proceeds. The Company will apply the net proceeds from the sale of the Securities as described in the Time of Sale Information and the Prospectus under the heading “Use of Proceeds.”

(j) No Stabilization. The Company will not take, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Securities.

(k) Record Retention . The Company will, pursuant to reasonable procedures developed in good faith, retain copies of each Issuer Free Writing Prospectus that is not filed with the Commission for three years after the Closing Date in accordance with Rule 433 under the Securities Act.

(l) Clear Market. For a period of 90 days after the date of the Prospectus, the Company will not (i) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, without the prior written consent of the J.P. Morgan Securities Inc. and Morgan Stanley & Co. Incorporated, other than (A) the Securities to be sold hereunder, (B) the shares of Common Stock to be sold by the Company concurrently herewith pursuant to an Underwriting Agreement, dated the date hereof, between J.P. Morgan Securities and Morgan Stanley & Co. Incorporated, as representatives of the several underwriters named therein, (C) the

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grant of options, awards of restricted stock and restricted stock units or the issuance of shares of Common Stock to employees or directors by the Company in the ordinary course of business or pursuant to any of the Company’s employee plans existing on the date of this Agreement, including, but not limited to, the Company’s employee stock option plan, the Company’s dividend reinvestment and stock purchase plan and the Company’s 401(k) plans and (D) the issuance by the Company of shares of Common stock upon the exercise of options granted under the Company’s employee plans. Notwithstanding the foregoing, if (1) during the last 17 days of the 90-day restricted period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (2) prior to the expiration of the 90-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 90-day period, the restrictions imposed by this Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

(m) Underlying Securities . The Company will reserve and keep available at all times, free of pre-emptive rights, shares of Common Stock for the purpose of enabling the Company to satisfy all obligations to issue the Underlying Securities upon conversion of the Securities.

(n) Exchange Listing. The Company will use all reasonable efforts to cause the Underlying Securities to be listed on the New York Stock Exchange.

5. Certain Agreements of the Underwriters . Each Underwriter hereby represents and agrees that:

(a) It has not and will not use, authorize use of, refer to, or participate in the planning for use of, any “free writing prospectus,” as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that, solely as a result of use by such Underwriter, would not trigger an obligation to file such free writing prospectus with the Commission pursuant to Rule 433, (ii) any Issuer Free Writing Prospectus listed on Schedule 2 hereto or prepared pursuant to Section 3(c) or Section 4(c) (including any electronic road show), or (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing.

(b) Notwithstanding the foregoing the Underwriters may use a term sheet substantially in the form of Schedule 3 hereto without the consent of the Company.

(c) The Representatives, on behalf of the several Underwriters, will, pursuant to reasonable procedures developed in good faith, retain copies of each Issuer Free Writing Prospectus that is not filed with the Commission for three years after the Closing Date in accordance with Rule 433 under the Securities Act.

(d) It is not subject to any pending proceeding under Section 8A of the Securities Act with respect to the offering of the Securities (and will promptly notify the Company if any such proceeding against it is initiated during the Prospectus Delivery Period).

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6. Conditions of Underwriters’ Obligations . The obligation of each Underwriter to purchase Underwritten Securities on the Closing Date or the Option Securities on the Additional Closing Date, as the case may be, as provided herein is subject to the performance by the Company of its covenants and other obligations hereunder and to the following additional conditions:

(a) Registration Compliance; No Stop Order. If a post-effective amendment to the Registration Statement is required to be filed under the Securities Act, such post-effective amendment shall have become effective, and the Representatives shall have received notice thereof, not later than 5:00