Exhibit 1.1

Execution Version

ATMOS ENERGY CORPORATION

4,558,404 Shares of Common Stock

Underwriting Agreement

November 28, 2017

Merrill Lynch, Pierce, Fenner & Smith

                     Incorporated

One Bryant Park

New York, New York 10036

J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Ladies and Gentlemen:

Atmos Energy Corporation, a Texas and Virginia corporation (the “ Company ”), proposes to issue and sell to the several underwriters listed in Schedule I hereto (the “ Underwriters ”) an aggregate of 4,558,404 shares of common stock, no par value, of the Company (the “ Shares ”). The shares of common stock of the Company to be outstanding after giving effect to the sale of the Shares are referred to herein as the “ Stock .”

The Company hereby confirms its agreement with the several Underwriters concerning the purchase and sale of the Shares, 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 (“ Rules and Regulations ”) of the Commission thereunder (collectively, the “ Securities Act ”), a registration statement (File No. 333-210424), including a prospectus, relating to the Shares. Such registration statement, as amended at the time it became effective, including the information, if any, deemed pursuant to Rule 430B under the Securities Act to be part of the registration statement at the time of its effectiveness (“ Rule 430 Information ”), is referred to herein as the “ Registration Statement .” As used in this underwriting agreement (this “ Agreement ”):

(a) “ Applicable Time ” means 6:30 P.M., New York City time, on November 28, 2017;

(b) “ Effective Date ” means any date as of which any part of the Registration Statement became effective under the Securities Act in accordance with the Rules and Regulations;

(c) “ General Use Issuer Free Writing Prospectus ” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors as evidenced by its being so specified in Annex A to this Agreement;

(d) “ Issuer Free Writing Prospectus ” means any “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations) prepared by or on behalf of the Company or used or referred to by the Company in connection with the offering of the Shares;

(e) “ Preliminary Prospectus ” means the base prospectus included in the Registration Statement together with any preliminary prospectus supplement relating to the Shares filed with the Commission pursuant to Rule 424(b) of the Securities Act;

(f) “ Pricing Disclosure Package ” means, as of the Applicable Time, the most recent Preliminary Prospectus dated November 28, 2017 together with any General Use Issuer Free Writing Prospectus filed or used by or on behalf of the Company on or before the Applicable Time as permitted by this Agreement and the information, if any, included on Exhibit D hereto; and

(g) “ Prospectus ” means the base prospectus included in the Registration Statement together with the final prospectus supplement relating to the Shares filed with the Commission pursuant to Rule 424(b) of the Securities Act.

Any reference in this Agreement to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Prospectus, as the case may be. Any reference to the “most recent Preliminary Prospectus” shall be deemed to refer to the base prospectus included in the Registration Statement, together with the latest preliminary prospectus supplement relating to the Shares filed with the Commission pursuant to Rule 424(b) prior to or on the date hereof (including, for purposes hereof, any documents incorporated by reference therein prior to or on the date hereof). Any reference to any amendment or supplement to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any document filed under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (the “ Exchange Act ”), after the date of such Preliminary Prospectus or the Prospectus, as the case may be, and incorporated by reference in such Preliminary Prospectus or the Prospectus, as the case may be; and any reference to any amendment to the Registration Statement shall be deemed to include any annual report of the Company on Form 10-K filed with the Commission pursuant to Section 13(a) or 15(d) of the Exchange Act after the Effective Date that is incorporated by reference in the Registration Statement.

2. Purchase of the Shares by the Underwriters .

(a) The Company agrees to issue and sell the Shares 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 number of Shares set forth opposite such Underwriter’s name in Schedule I hereto at a price per share of $86.79 (the “ Purchase Price ”).

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

(c) Payment for the Shares shall be made by wire transfer in immediately available funds to the account specified by the Company to the Underwriters in the case of the Shares, at the offices of Shearman & Sterling LLP, 599 Lexington Avenue, New York, New York 10012 at 10:00 A.M., New York City time, on December 1, 2017, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Underwriters and the Company may agree upon in writing. The time and date of such payment for the Shares is referred to herein as the “ Closing Date .”

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Payment for the Shares to be purchased on the Closing Date shall be made against delivery to the Underwriters for their respective accounts of the Shares to be purchased on the Closing Date with any transfer taxes payable in connection with the sale of such Shares duly paid by the Company. Delivery of the Shares shall be made through the facilities of The Depository Trust Company (“ DTC ”) unless the Underwriters shall otherwise instruct.

(d) 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 the offering of Shares 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. Additionally, none of the Underwriters 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 the Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by the Underwriters of the Company, the transactions contemplated hereby 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.

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

(a) The Registration Statement (i) has been prepared by the Company in conformity with the requirements of the Securities Act and the Rules and Regulations; (ii) has been filed with the Commission under the Securities Act; and (iii) is effective under the Securities Act. Copies of the Registration Statement have been delivered by the Company to the Underwriters.

(b) The Commission has not issued any stop order preventing or suspending the use of any Preliminary Prospectus or the Prospectus or suspending the effectiveness of the Registration Statement, and no proceeding or examination for such purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Shares has been instituted or, to the knowledge of the Company, threatened by the Commission. The Commission has not notified the Company of any objection to the use of the form of the Registration Statement.

(c) At the time of filing the Registration Statement and, if applicable, at the time of the most recent amendment thereto for purposes of complying with Section 10(a)(3) of the Securities Act, the Company was a “well-known seasoned issuer” (as defined in Rule 405 of the Rules and Regulations) eligible to use Form S-3 for the offering of the Shares, including not having been an “ineligible issuer” (as defined in Rule 405 of the Rules and Regulations) at any such time. The Registration Statement is an “automatic shelf registration statement” (as defined in Rule 405 of the Rules and Regulations) and was filed not earlier than the date that is three years prior to the Closing Date.

(d) The Registration Statement conformed in all material respects on the Effective Date and will conform in all material respects on the Closing Date and any amendment to the Registration Statement filed after the date hereof will conform in all material respects when filed to the requirements of the Securities Act and the Rules and Regulations. The Preliminary Prospectus conformed, and the Prospectus will conform, in all material respects when filed with the Commission pursuant to Rule 424(b) and on the Closing Date to the requirements of the Securities Act and the Rules and Regulations. The documents incorporated by reference in any Preliminary Prospectus or the Prospectus conformed, and any further documents so incorporated will conform, when filed with the Commission, in all material respects, to the requirements of the Exchange Act or the Securities Act, as applicable, and the rules and regulations of the Commission thereunder.

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(e) The Registration Statement did not, as of the Effective Date, 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 that no representation or warranty is made as to information contained in or omitted from the Registration Statement in reliance upon and in conformity with written information furnished to the Company by the Underwriters specifically for inclusion therein, which information is specified in Section 7(b).

(f) The Prospectus will not, as of its date and on the Closing Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that no representation or warranty is made as to information contained in or omitted from the Prospectus in reliance upon and in conformity with written information furnished to the Company by the Underwriters specifically for inclusion therein, which information is specified in Section 7(b).

(g) The documents incorporated by reference in any Preliminary Prospectus or the Prospectus did not, and any further documents filed and incorporated by reference therein will not, when filed with the Commission, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. There are no contracts or documents that are required to be described in the Registration Statement, the Prospectus or the documents incorporated by reference therein or to be filed as exhibits thereto that have not been so described and filed as required.

(h) The Pricing Disclosure Package did not, as of the Applicable Time, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that no representation or warranty is made as to information contained in or omitted from the Pricing Disclosure Package in reliance upon and in conformity with written information furnished to the Company by the Underwriters specifically for inclusion therein, which information is specified in Section 7(b).

(i) Each Issuer Free Writing Prospectus (including, without limitation, any road show that is a free writing prospectus under Rule 433), when considered together with the Pricing Disclosure Package as of the Applicable Time, did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(j) Each Issuer Free Writing Prospectus conformed or will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations on the date of first use, and the Company has complied with any filing requirements applicable to such Issuer Free Writing Prospectus pursuant to the Securities Act and the Rules and Regulations. Each Issuer Free Writing Prospectus does not and will not conflict with the information contained in the Registration Statement, the most recent Preliminary Prospectus or the Prospectus. The Company has not made any offer relating to the Shares that would constitute an Issuer Free Writing Prospectus without the prior written consent of the Underwriters. The Company has retained in accordance with the Rules and Regulations all Issuer Free Writing Prospectuses that were not required to be filed pursuant to the Rules and Regulations.

(k) The Company has been duly organized and is validly existing as a corporation in good standing under the laws of the State of Texas and the Commonwealth of Virginia and has corporate power and authority to own, lease and operate its properties and to conduct its business as described in the most recent Preliminary Prospectus and to enter into and perform its obligations under this Agreement; and the

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Company is duly qualified as a foreign corporation to transact business and is in good standing in each other jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure so to qualify or to be in good standing would not result in a material adverse change, or a development known to the Company involving a prospective material adverse change, in the condition, financial or otherwise, or in the earnings, business affairs, management or business prospects of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business (a “ Material Adverse Effect ”).

(l) Each “significant subsidiary” (as such term is defined in Rule 405 of the Securities Act) of the Company (each a “ Subsidiary ” and, collectively, the “Subsidiaries”), if any, (a) has been duly organized and is validly existing as an entity in good standing under the laws of the jurisdiction of its formation, (b) has corporate or limited liability company power and authority, as applicable, to own, lease and operate its properties and to conduct its business as described in the most recent Preliminary Prospectus and (c) is duly qualified as a foreign entity to transact business and is in good standing in each jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except in the cases of clauses (b) and (c) where the failure to have such power and authority or to so qualify or to be in good standing would not result in a Material Adverse Effect. The only Subsidiaries of the Company are the subsidiaries listed on Schedule II, and the Company does not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed on Schedule III.

(m) The authorized, issued and outstanding capital stock of the Company is as set forth in the most recent Preliminary Prospectus and the Prospectus (except for subsequent issuances, if any, pursuant to reservations, agreements, acquisitions or employee benefit plans each referred to in the most recent Preliminary Prospectus and the Prospectus or pursuant to the exercise of options or share unit awards, each referred to in the most recent Preliminary Prospectus and the Prospectus). The shares of issued and outstanding capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable; none of the outstanding shares of capital stock of the Company were issued in violation of the preemptive or other similar rights of any securityholder of the Company.

(n) All of the issued and outstanding capital stock or limited liability company membership interests, as the case may be, of each Subsidiary have been duly authorized and validly issued, are fully paid and non assessable and are owned by the Company, directly or through subsidiaries, free and clear of any security interest, mortgage, pledge, lien, encumbrance, claim or equity except for such liens, encumbrances, equities or claims as would not, in the aggregate, reasonably be expected to have a Material Adverse Effect; none of the outstanding shares of capital stock or limited liability company membership interests, as the case may be, of any Subsidiary were issued in violation of the preemptive or similar rights of any securityholder of such Subsidiary.

(o) The Shares to be issued and sold by the Company hereunder have been duly authorized and, when issued and delivered and paid for as provided herein, will be duly and validly issued, will be fully paid and non-assessable and will conform in all material respects to the descriptions thereof in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and the issuance of the Shares is not subject to any preemptive or similar rights.

(p) The Company has all requisite corporate power and authority to execute, deliver and perform its obligations under this Agreement. This Agreement has been duly and validly authorized, executed and delivered by the Company.

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(q) Neither the Company nor any of its subsidiaries is in violation of its charter, bylaws or other organizational documents or in default in the performance or observance of any obligation, agreement, covenant or condition contained in any contract, indenture, mortgage, deed of trust, loan or credit agreement, note, lease or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which it or any of them may be bound, or to which any of the property or assets of the Company or any subsidiary is subject (collectively, “ Agreements and Instruments ”) except for such defaults that would not result in a Material Adverse Effect; and (i) the execution, delivery and performance of this Agreement and any other agreement or instrument entered into or issued or to be entered into or issued by the Company in connection with the consummation of the transactions contemplated in each of the most recent Preliminary Prospectus and the Prospectus (including the issuance and sale of the Shares and the use of the proceeds from the sale of the Shares as described in each of the most recent Preliminary Prospectus and the Prospectus under the caption “Use of Proceeds”) and (ii) compliance by the Company with its obligations hereunder and thereunder have been duly authorized by all necessary corporate or other action on the part of the Company and any of the subsidiaries and do not and will not, whether with or without the giving of notice or passage of time or both, conflict with or constitute a breach of, or default or Repayment Event (as defined below) under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any subsidiary pursuant to, the Agreements and Instruments (except for such conflicts, breaches or defaults or liens, charges, encumbrances or a Repayment Event that would not result in a Material Adverse Effect), nor will such action result in any violation of (y) the provisions of the charter, bylaws or other organizational documents of the Company or any subsidiary or (z) any applicable law, statute, rule, regulation, judgment, order, writ or decree of any government, government instrumentality or court, domestic or foreign, having jurisdiction over the Company or any subsidiary or any of their assets, properties or operations except, with respect to (z), as would not result in a Material Adverse Effect. As used herein, a “ Repayment Event ” means any event or condition which gives the holder of any note, debenture or other evidence of indebtedness (or any person acting on such holder’s behalf) the right, whether with or without giving of notice or passage of time or both, to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any subsidiary.

(r) No labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent, and the Company is not aware of any existing or imminent labor disturbance by the employees of any of its or any subsidiary’s principal suppliers, manufacturers, customers or contractors, which, in either case, may reasonably be expected to result in a Material Adverse Effect.

(s) There is no action, suit, proceeding, inquiry or investigation before or brought by any court or governmental agency or body, domestic or foreign, now pending against, or, to the knowledge of the Company, threatened against or affecting the Company or any of its subsidiaries, which is required to be disclosed in the most recent Preliminary Prospectus (other than as disclosed therein), or which might reasonably be expected to result in a Material Adverse Effect, or which might reasonably be expected to affect the properties, assets or operations of the Company and its subsidiaries, except what does not result in a Material Adverse Effect, or the consummation of the transactions contemplated in this Agreement or the performance by the Company and its subsidiaries of its obligations hereunder.

(t) The Company and each of its Subsidiaries own or possess or have the right to use, or can acquire on reasonable terms, adequate patents, patent rights, licenses, inventions, copyrights, know how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), trademarks, service marks, trade names or other intellectual property (collectively, “ Intellectual Property ”) necessary to carry on the business now operated by them the absence of which would have a Material Adverse Effect, and neither the Company nor any of its subsidiaries has received any notice or is otherwise aware of any infringement of or conflict with asserted rights of others with respect to any Intellectual Property or of any facts or circumstances which would render any Intellectual Property invalid or inadequate to protect the interest of the Company or any of its subsidiaries therein, and which infringement, conflict, invalidity or inadequacy would result in a Material Adverse Effect.

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(u) There have been issued and, at the Applicable Time and the Closing Date, there shall be in full force and effect orders or authorizations of the regulatory authorities of the states of Colorado, Kentucky and Virginia authorizing the issuance and sale of the Shares on terms herein set forth or contemplated, and no other consent, approval, authorization, order, license, registration or qualification of or with any court or governmental or regulatory authority is required for the execution, delivery and performance by the Company of this Agreement, the issuance and sale of the Shares and the consummation of the transactions contemplated by this Agreement, except for the registration of the Shares under the Securities Act and such consents, approvals, authorizations, orders and registrations or qualifications as may be required by the Financial Industry Regulatory Authority, Inc. (“ FINRA ”) and under applicable state securities laws in connection with the purchase and distribution of the Shares by the Underwriters.

(v) The Company and its subsidiaries possess such permits, licenses, approvals, consents, and other authorizations (collectively, “ Governmental Licenses ”) issued by the appropriate federal, state, local or foreign regulatory agencies or bodies necessary to conduct the business now operated by them, except where the failure to do so would not have a Material Adverse Effect; the Company and its subsidiaries are in compliance with the terms and conditions of all such Governmental Licenses, except where the failure so to comply would not, singly or in the aggregate, have a Material Adverse Effect; all of the Governmental Licenses are valid and in full force and effect, except when the invalidity of such Governmental Licenses or the failure of such Governmental Licenses to be in full force and effect would not have a Material Adverse Effect; and neither the Company nor any of its subsidiaries has received any notice of proceedings relating to the revocation or modification of any such Governmental Licenses which, singly or in the aggregate, would result in a Material Adverse Effect.

(w) There are no persons or entities with registration rights or other similar rights to have any securities registered under the Registration Statement who have not properly waived such rights in connection with the securities registered pursuant to the Registration Statement and in connection with this offering of Shares.

(x) The Company and its subsidiaries have good title to all real property owned by the Company and its subsidiaries and good title to all other properties owned by them, in each case, free and clear of all mortgages, pledges, liens, security interests, claims, restrictions or encumbrances of any kind except such as (a) are described in the most recent Preliminary Prospectus or (b) would not singly or in the aggregate have a Material Adverse Effect. All of the leases and subleases of the Company and its subsidiaries under which the Company or any of its subsidiaries holds properties described in the most recent Preliminary Prospectus are in full force and effect, except as would not result in a Material Adverse Effect.

(y) The Company has not sold or issued any securities that would be integrated with the offering of the Shares contemplated by this Agreement pursuant to the Securities Act, the Rules and Regulations or the interpretations thereof by the Commission.

(z) The financial statements of the Company included or incorporated by reference in the Registration Statement, the most recent Preliminary Prospectus and the Prospectus, together with the related schedules and notes, present fairly in all material respects the financial position of the Company and its consolidated subsidiaries at the dates indicated and the statement of operations, stockholders’ equity and cash flows of the Company and its consolidated subsidiaries for the periods specified; said financial statements have been prepared in conformity with generally accepted accounting principles

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(“ GAAP ”) applied on a consistent basis throughout the periods involved. The supporting schedules, if any, included in the Registration Statement and incorporated by reference in the most recent Preliminary Prospectus and the Prospectus with respect to the Company, when considered in relation to the financial statements taken as a whole, present fairly, in all material respects in accordance with GAAP, the financial information set forth therein. The selected financial data and the summary financial information included or incorporated by reference in the most recent Preliminary Prospectus and the Prospectus present fairly, in all material respects, the information shown therein and have been compiled on a basis consistent with that of the audited financial statements of the Company.

(aa) Ernst & Young LLP, who have audited financial statements and supporting schedules of the Company and its consolidated subsidiaries incorporated by reference in the most recent Preliminary Prospectus and in the Registration Statement, whose report is incorporated by reference in the most recent Preliminary Prospectus and in the Registration Statement, who have audited the Company’s internal control over financial reporting and who have delivered the initial letter referred to in Section 6(f) hereof, are independent registered public accountants as required by the Securities Act and the Rules and Regulations.

(bb) The interactive data in the eXtensible Business Reporting Language incorporated by reference in the Registration Statement fairly presents the information called for in all material respects and has been prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(cc) None of the Company or any of its subsidiaries are, or as of the Closing Date and upon the issuance and sale of the Shares and the application of the proceeds therefrom as described under “Use of Proceeds” in the most recent Preliminary Prospectus and the Prospectus, will be, (i) an “investment company” or an entity “controlled” by an “investment company” as such terms are defined in the Investment Company Act of 1940, as amended (the “ Investment Company Act ”) and the rules and regulations of the Commission thereunder or (ii) a “business development company” (as defined in Section 2(a)(48) of the Investment Company Act).

(dd) (i) Each “employee benefit plan” (within the meaning of Section 3(3) of the Employee Retirement Security Act of 1974, as amended (“ ERISA ”)) for which the Company or any member of its “ Controlled Group ” (defined as any organization which is a member of a controlled group of corporations within the meaning of Section 414(b) or (c) of the Internal Revenue Code of 1986, as amended (the “ Code ”)) would have any liability (each a “ Plan ”) has been maintained in compliance in all respects with its terms and with the requirements of all applicable statutes, rules and regulations including ERISA and the Code except where failure to do so would not have a Material Adverse Effect; (ii) with respect to each Plan subject to Title IV of ERISA (a) no “reportable event” (within the meaning of Section 4043(c) of ERISA) has occurred or is reasonably expected to occur that would result in a Material Adverse Effect, (b) no “accumulated funding deficiency” (within the meaning of Section 302 of ERISA or Section 412 of the Code), whether or not waived, has occurred or is reasonably expected to occur that would result in a Material Adverse Effect, (c) the fair market value of the assets under each Plan exceeds the actuarial present value of the benefits accrued under such Plan (determined based on those assumptions used to fund such Plan) except where failure to do so would not have a Material Adverse Effect, and (d) neither the Company nor any member of its Controlled Group has incurred, or reasonably expects to incur, any liability under Title IV of ERISA (other than contributions to the Plan or premiums to the Pension Benefit Guaranty Corporation in the ordinary course and without default) in respect of a Plan (including a “multiemployer plan” within the meaning of Section 4001(c)(3) of ERISA) that would result in a Material Adverse Effect; and (iii) each Plan that is intended to be qualified under Section 401(a) of the Code has received a favorable determination letter from the Internal Revenue Service as to its qualified status and nothing has occurred, whether by action or by failure to act, which would cause the loss of such qualification that would result in a Material Adverse Effect.

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(ee) The Company is in compliance, in all material respects, with the provisions of the Sarbanes-Oxley Act of 2002 to the extent currently applicable.

(ff) The Company and each of its subsidiaries have filed all federal, state and local income and franchise tax returns required to be filed through the date hereof and have paid all taxes due thereon, except such as are being contested in good faith by appropriate proceedings or where the failure to do so would not have a Material Adverse Effect, and no tax deficiency has been determined adversely to the Company or any of its subsidiaries that has had, and the Company does not have any knowledge of any tax deficiency that would have, a Material Adverse Effect.

(gg) The Company and its subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as is adequate for the conduct of their respective businesses and the value of their respective properties, except where the failure to do so would not reasonably be expected to have a Material Adverse Effect.

(hh) Except as would not result in a Material Adverse Effect, (A) neither the Company nor any of its subsidiaries is in violation of any federal, state, local or foreign statute, law, rule, regulation, ordinance, code, permit, policy or rule of common law or any judicial or administrative interpretation thereof, including any judicial or administrative order, consent, decree or judgment, relating to pollution or protection of human health, the environment (including, without limitation, ambient air, surface water, groundwater, land surface or subsurface strata) or wildlife, including, without limitation, laws and regulations relating to the release or threatened release of chemicals, pollutants, contaminants, wastes, toxic substances, hazardous substances, petroleum or petroleum products (collectively, “ Hazardous Materials ”) or to the manufacture, processing, distribution, use, treatment, storage, disposal, transport or handling of Hazardous Materials (collectively, “ Environmental Laws ”); (B) the Company and its subsidiaries have all permits, authorizations and approvals required under any applicable Environmental Laws and are each in compliance with their requirements; (C) there are no pending or, to the knowledge of the Company, threatened administrative, regulatory or judicial actions, suits, demands, demand letters, claims, liens, notices of noncompliance or violation, investigation or proceedings relating to any Environmental Law against the Company or any of its subsidiaries; and (D) there are no events or circumstances that might reasonably be expected to form the basis of an order for clean-up or remediation, or an action, suit or proceeding by any private party or governmental body or agency, against or affecting the Company or any of its subsidiaries relating to Hazardous Materials or any Environmental Laws, except as disclosed in the Preliminary Prospectus.

(ii) The Company maintains a system of internal control over financial reporting (as such term is defined in Rule 13a-15(f) of the Exchange Act) that complies with the requirements of the Exchange Act and has been designed by the Company’s principal executive officer and principal financial officer, or under their supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with GAAP. 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. Since the date of the latest audited financial statements included or incorporated by reference in the most recent Preliminary 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. The Company maintains disclosure controls and procedures (as such term is defined in Rule 13a-15(e) of the Exchange Act) that comply with the requirements of the Exchange Act and such disclosure controls and procedures have been designed to provide reasonable assurance that material information relating to the Company and its subsidiaries that is required to be disclosed in the reports the Company files, furnishes, submits or otherwise provides to the Commission under the Exchange Act is made known to the Company’s principal executive officer and principal financial officer by others within those entities in such a manner as to allow timely decisions regarding the required disclosure; such disclosure controls and procedures are effective.

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(jj) The Company has not distributed and, prior to the latest to occur of the Closing Date or completion of the distribution of the Shares, will not distribute any offering material in connection with the offering and sale of the Shares other than any Preliminary Prospectus, the Prospectus or any Issuer Free Writing Prospectus to which the Underwriters have consented in accordance with Section 3(j) or 4(c).

(kk) Any certificate signed by any officer of the Company and delivered to the Underwriters or counsel for the Underwriters in connection with the offering of the Shares shall be deemed a representation and warranty by the Company, as to matters covered thereby on the date of such certificate, to each Underwriter.

(ll) Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, employee, agent, affiliate 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 or taken an act in furtherance of an offer, promise or authorization of any direct or indirect unlawful payment to any foreign or domestic government official or employee, including of any government-owned or controlled entity, or any person acting in an official capacity for or on behalf of any of the foregoing, or any political party or party official or candidate for political office; (iii) violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977, as amended; or (iv) made, offered, agreed, requested or taken an act in furtherance of any unlawful bribe, rebate, payoff, influence payment, kickback or other unlawful payment.

(mm) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements, including those of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the applicable money laundering statutes of all jurisdictions where the Company or any of its subsidiaries conducts business, the rules and regulations thereunder and any related or similar rules, regulations or guidelines issued, administered or enforced by any governmental agency (collectively, the “ Anti-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 Anti-Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(nn) Neither the Company nor any of its subsidiaries, nor, to the knowledge of the Company, any director, officer, employee, agent, affiliate or other person associated with or acting on behalf of the Company or any of its subsidiaries is currently subject to any sanctions administered or enforced by the U.S. government, (including, without limitation, the Office of Foreign Assets Control of the U.S. Department of the Treasury or the U.S. Department of State and including, without limitation, the designation as a “specially designated national” or “blocked person”), (collectively, “ Sanctions ”); and the Company will not directly or indirectly use the proceeds of the offering of the Shares hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity (i) to fund or facilitate any activities of or business with any person that, at the time of such funding or facilitation, is subject to Sanctions, or (ii) in any other manner that will result in a violation by any person (including any person participating in the transaction, whether as underwriter, advisor, investor or otherwise) of Sanctions. Neither the Company nor any of its subsidiaries have any operations or transact any business outside of the United States. All of the proceeds from the offering will be used in the United States.

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

(a) Required Filings. The Company will file the final Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430B under the Securities Act, will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; will file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Shares. The Company will pay the registration fee for this offering within the time period required by Rule 456(b)(1) under the Securities Act (without giving effect to the proviso therein) and in any event prior to the Closing Date.

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

(c) Amendments or Supplements, Issuer Free Writing Prospectuses. During the Prospectus Delivery Period, before 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 Underwriters and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not 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 Underwriters reasonably object.

(d) Notice to the Underwriters. The Company will advise the Underwriters 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 or any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed or distributed; (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) 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, any of the Pricing Disclosure Package 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 or development within the Prospectus Delivery Period as a result of which the Prospectus, any of the Pricing Disclosure Package 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 required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus, the Pricing Disclosure Package or any such 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 Shares for offer and sale

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in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and the Company will use its best 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, any of the Pricing Disclosure Package or the Prospectus or suspending any such qualification of the Shares and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

(e) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event or development 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 required to be stated therein or 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 law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriters and such dealers as the Underwriters may designate such amendments or supplements to the Prospectus (or any document to be filed with the Commission and incorporated by reference therein) as may be necessary so that the statements in the Prospectus as so amended or supplemented (or any document to be filed with the Commission and incorporated by reference therein) 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 law, and (2) if at any time prior to the Closing Date, (i) any event or development shall occur or condition shall exist as a result of which the Pricing Disclosure Package 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 Pricing Disclosure Package is delivered to a purchaser, not misleading, or (ii) it is necessary to amend or supplement the Pricing Disclosure Package to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and such dealers as the Underwriters may designate such amendments or supplements to the Pricing Disclosure Package (or any document to be filed with the Commission and incorporated by reference therein) as may be necessary so that the statements in the Pricing Disclosure Package as so amended or supplemented will not, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, be misleading or so that the Pricing Disclosure Package will comply with law.

(f) Blue Sky Compliance. The Company will qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Underwriters shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Shares; 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.

(g) Clear Market. For a period of 90 days after the date of the Prospectus, the Company will not (i) offer, pledge, 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, or file with the Commission a registration statement under the Securities Act relating to, any shares of Stock or any securities convertible into or exercisable or exchangeable for Stock, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing, 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 Stock or any such other securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise, without the prior written consent of the Underwriters, other than (A) the Shares to be sold hereunder; (B) any shares of Stock issued upon the exercise of options granted under Company Stock Plans or upon the vesting of restricted

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stock units granted under Company Stock Plans and the Company’s Retirement Savings Plan and Trust; (C) the grant of restricted stock unit awards under Company Stock Plans; and (D) the issuance of shares of Stock pursuant to the Company’s Direct Stock Purchase Plan. For the purposes of this Agreement, “ Company Stock Plans ” means any stock option plans or other equity incentive plans of the Company and its subsidiaries as such plans are in effect on the date of this Agreement.

(h) Use of Proceeds . The Company will apply the net proceeds from the sale of the Shares as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the heading “Use of Proceeds.”

(i) 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 Stock.

(j) Reports . During the Prospectus Delivery Period, the Company will furnish to the Underwriters, as soon as they are available, copies of all reports or other communications (financial or other) furnished to holders of the Shares, and copies of any reports and financial statements furnished to or filed with the Commission or any national securities exchange or automatic quotation system; provided the Company will be deemed to have furnished such reports and financial statements to the Underwriters to the extent they are filed on the Commission’s Electronic Data Gathering, Analysis, and Retrieval system.

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

(a) It has not used, authorized use of, referred to or participated in the planning for use of, 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 contains no “issuer information” (as defined in Rule 433(h)(2) under the Securities Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Annex A or prepared pursuant to Section 3(j) or Section 4(c) above (including any electronic road show), or (iii) any free writing prospectus prepared by such Underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “ Underwriter Free Writing Prospectus ”).

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

6. Conditions of Underwriters’ Obligations. The obligation of each Underwriter to purchase the Shares on the Closing Date 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 . No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose, pursuant to Rule 401(g)(2) or pursuant to Section 8A under the Securities Act shall be pending before or threatened by the Commission; the Prospectus and each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Underwriters.

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(b) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date; and the statements of the Company and its officers made in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date.

(c) No Downgrade. Subsequent to the earlier of (A) the Applicable Time and (B) the execution and delivery of this Agreement, if there are any debt securities of the Company or any of its subsidiaries that are rated by a “nationally recognized statistical rating organization,” as such term is defined under Section 3(a)(62) under the Exchange Act, (i) no downgrading shall have occurred in the rating accorded any such debt securities, and (ii) no such organization shall have publicly announced that it has under surveillance or review, with possible negative implications for its rating of any such debt securities.

(d) No Material Adverse Change. There has not been any change, or any development known to the Company involving a prospective change, in the condition, financial or otherwise, or in the earnings, business affairs, management or business prospects of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, the effect of which is, in the judgment of the Underwriters, so material and adverse as to make it impracticable or inadvisable to proceed with the public offering or the delivery of the Shares being delivered on the Closing Date on the terms and in the manner contemplated in the Prospectus.

(e) Officer’s Certificate. The Underwriters shall have received on and as of the Closing Date a certificate of the chief executive officer or chief financial officer of the Company stating that:

i. the representations, warranties and agreements of the Company in this Agreement are true and correct, and the Company has complied with all its agreements contained herein and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date;

ii. no stop order suspending the effectiveness of the Registration Statement has been issued; no proceedings or examination for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Shares have been instituted or, to the knowledge of such officers, threatened; and the Commission has not notified the Company of any objection to the use of the form of the Registration Statement or any post-effective amendment thereto; and

iii. there has been no material adverse change, or a development known to the Company involving a prospective material adverse change, in the condition, financial or otherwise, or in the earnings, business affairs, management or business prospects of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business.

(f) Comfort Letters. On the date of this Agreement and on the Closing Date, Ernst & Young LLP shall have furnished to the Underwriters, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus; provided, that the letter delivered on the Closing Date shall use a “cut-off” date no more than three business days prior to the Closing Date.

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(g) Opinion and 10b-5 Statement of Outside Counsel for the Company . Gibson, Dunn & Crutcher LLP, counsel for the Company, shall have furnished to the Underwriters, at the request of the Company, their written opinion and 10b-5 statement, dated the Closing Date and addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters.

(h) Opinion and 10b-5 Statement of In-house Counsel for the Company . The General Counsel of the Company shall have furnished to the Underwriters, at the request of the Company, his or her written opinion and 10b-5 statement, dated the Closing Date and addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters, to the effect set forth in Exhibit A hereto.

(i) Opinion of Virginia Counsel for the Company . Hunton & Williams LLP, as Virginia counsel for the Company, shall have furnished to the Underwriters, at the request of the Company, their written opinion, dated the Closing Date and addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters, to the effect set forth in Exhibit B hereto.

(j) Opinion and 10b-5 Statement of Counsel for the Underwriters . The Underwriters shall have received on and as of the Closing Date an opinion and 10b-5 statement of Shearman & Sterling LLP, counsel for the Underwriters, with respect to such matters as the Underwriters may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

(k) No Legal Impediment to Issuance . No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the Closing Date, prevent the issuance or sale of the Shares; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date, prevent the issuance or sale of the Shares.

(l) Good Standing . The Underwriters shall have received on and as of the Closing Date satisfactory evidence of the good standing of the Company in its jurisdictions of organization and its good standing as a foreign entity in such other jurisdictions as the Underwriters may reasonably request, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

(m) Exchange Listing . The Shares to be delivered on the Closing Date shall have been approved for listing on the New York Stock Exchange, subject to official notice of issuance.

(n) Lock-up Agreements . The “lock-up” agreements, each substantially in the form of Exhibit C hereto, between you and the executive officers and directors of the Company relating to sales and certain other dispositions of shares of Stock or certain other securities, delivered to you on or before the date hereof, shall be full force and effect on the Closing Date.

(o) Additional Documents . On or prior to the Closing Date, the Company shall have furnished to the Underwriters such further certificates and documents as the Underwriters may reasonably request.

All opinions, letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

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7. Indemnification and Contribution .

(a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors, officers and employees and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, reasonable legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, (ii) or any untrue statement or alleged untrue statement of a material fact contained in the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus, any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Securities Act, any road show as defined in Rule 433(h) under the Securities Act (a “road show”) or any Pricing Disclosure Package (including any Pricing Disclosure Package that has subsequently been amended), or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (b) below.

(b) Indemnification of the Company. Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers, its affiliates, its employees and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in paragraph (a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to such Underwriter furnished to the Company in writing by such Underwriter expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus, any road show or any Pricing Disclosure Package (including any Pricing Disclosure Package that has subsequently been amended), it being understood and agreed upon that the only such information furnished by any Underwriter consists of the following information in the Prospectus furnished on behalf of each Underwriter: the fourth paragraph and the seventh paragraph, each under the caption “Underwriting.”

(c) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “ Indemnified Person ”) shall promptly notify the person against whom such indemnification may be sought (the “ Indemnifying Person ”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under paragraph (a) or (b) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided , further , that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under paragraph (a) or (b) above. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person (who shall not, without the consent of the Indemnified Person, be counsel to the Indemnifying Person) to represent the Indemnified Person in such proceeding and shall pay

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the reasonable fees and expenses of such counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interest between them. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceedings in the same jurisdiction, be liable for the reasonable fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be paid or reimbursed as they are incurred. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by the Underwriters and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

(d) Contribution. If the indemnification provided for in paragraphs (a) and (b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and the Underwriters on the other, from the offering of the Shares or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company, on the one hand, and the Underwriters on the other, in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company, on the one hand, and the Underwriters on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Shares and the total underwriting discounts and commissions received by the Underwriters in connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Shares. The relative fault of the Company, on the one hand, and the Underwriters on the other, shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

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(e) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to paragraph (d) above were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of paragraphs (d) and (e), in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Shares exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to paragraphs (d) and (e) are several in proportion to their respective purchase obligations hereunder and not joint.

(f) Non-Exclusive Remedies. The remedies provided for in paragraphs (a) through (e) of this Section 7 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any Indemnified Person at law or in equity.

8. Effectiveness of Agreement . This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

9. Termination . The obligations of the Underwriters hereunder may be terminated by the Underwriters by notice given to and received by the Company prior to delivery of and payment for the Shares if subsequent to the execution and delivery of this Agreement there shall have occurred any of the following: (i) trading in securities generally on the New York Stock Exchange or in the over-the-counter market, or trading in any securities of the Company on any exchange or in the over-the-counter market, shall have been suspended or materially limited or the settlement of such trading generally shall have been materially disrupted or minimum prices shall have been established on any such exchange or such market by the Commission, by such exchange or by any other regulatory body or governmental authority having jurisdiction, (ii) a banking moratorium shall have been declared by federal or New York, Texas or Virginia authorities or there shall have occurred any material disruption in commercial banking, securities settlement or clearance services in the United States, (iii) the United States shall have become engaged in hostilities, there shall have been an escalation in hostilities involving the United States or there shall have been a declaration of a national emergency or war by the United States or (iv) there shall have occurred such a material adverse change in general economic, political or financial conditions, including, without limitation, as a result of terrorist activities after the date hereof (or the effect of international conditions on the financial markets in the United States shall be such), in the case of each of the foregoing subsections (i)  through (iv) , as to make it, in the judgment of the Underwriters, impracticable or inadvisable to proceed with the public offering, sale or delivery of the Shares being delivered on the Closing Date on the terms and in the manner contemplated in the Pricing Disclosure Package and the Prospectus.

10. Defaulting Underwriter .

(a) If, on the Closing Date, any Underwriter defaults on its obligation to purchase the Shares that it has agreed to purchase hereunder on such date, the non-defaulting Underwriters may in their discretion arrange for the purchase of such Shares by other persons satisfactory to the Company on the terms contained in this Agreement. If, within 36 hours after any such default by any Underwriter, the

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non-defaulting Underwriters do not arrange for the purchase of such Shares, then the Company shall be entitled to a further period of 36 hours within which to procure other persons satisfactory to the non-defaulting Underwriters to purchase such Shares on such terms. If other persons become obligated or agree to purchase the Shares of a defaulting Underwriter, either the non-defaulting Underwriters or the Company may postpone the Closing Date for up to five full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “ Underwriter ” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule I hereto that, pursuant to this Section 10, purchases Shares that a defaulting Underwriter agreed but failed to purchase.

(b) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date does not exceed one-eleventh of the aggregate number of Shares to be purchased on such date, then the Company shall have the right to require each non-defaulting Underwriter to purchase the number of Shares that such Underwriter agreed to purchase hereunder on such date plus such Underwriter’s pro rata share (based on the number of Shares that such Underwriter agreed to purchase on such date) of the Shares of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

(c) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date exceeds one-eleventh of the aggregate number of Shares to be purchased on such date, or if the Company shall not exercise the right described in paragraph (b) above, then this Agreement shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 10 shall be without liability on the part of the Company, except that the Company will continue to be liable for the payment of expenses as set forth in Section 11 hereof and except that the provisions of Section 7 hereof shall not terminate and shall remain in effect.

(d) Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company or any non-defaulting Underwriter for damages caused by its default.

11. Payment of Expenses .

(a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid upon demand all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the authorization, issuance, sale, preparation and delivery of the Shares and any taxes payable in that connection; (ii) the costs incident to the preparation, printing and filing under the Securities Act of the Registration Statement, the Preliminary Prospectus, any Issuer Free Writing Prospectus, any Pricing Disclosure Package and the Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the fees and expenses of the Company’s counsel and independent accountants; (iv) the fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Shares under the state or foreign securities or blue sky laws of such jurisdictions as the Underwriters may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related reasonable fees and expenses of counsel for the Underwriters); (v) the cost of preparing stock certificates; (vi) the costs and charges of any transfer agent and any registrar; (vii) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, FINRA; (viii) all expenses incurred by the Company in connection with any “road show” presentation to potential investors and (ix) all expenses and application fees related to the listing of the Shares on the New York Stock Exchange.

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(b) If (i) this Agreement is terminated pursuant to Section 9, (ii) the Company for any reason fails to tender the Shares for delivery to the Underwriters or (iii) the Underwriters decline to purchase the Shares for any reason permitted under this Agreement, the Company agrees to reimburse the Underwriters for all out-of-pocket costs and expenses (including the reasonable fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

(c) Except as otherwise expressly provided in Section 7 of this Agreement and this Section 11, the Underwriters shall pay their own costs and expenses, including the costs and expenses of their counsel, any transfer taxes on the Shares which they may sell and the expenses of advertising any offering of the Shares made by the Underwriters.

12. Persons Entitled to Benefit of Agreement . This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and any controlling persons referred to in Section 7 hereof. Nothing in this Agreement is intended or shall be construed to give any other person any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein. No purchaser of Shares from any Underwriter shall be deemed to be a successor merely by reason of such purchase.

13. Survival . The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Underwriters contained in this Agreement or made by or on behalf of the Company or the Underwriters pursuant to this Agreement or any certificate delivered pursuant hereto shall survive the delivery of and payment for the Shares and shall remain in full force and effect, regardless of any termination of this Agreement or any investigation made by or on behalf of the Company or the Underwriters.

14. Certain Defined Terms . For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) the term “business day” means any day other than a day on which banks are permitted or required to be closed in New York City; and (c) the term “subsidiary” has the meaning set forth in Rule 405 under the Securities Act.

15. Miscellaneous .

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

(b) Notices . All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, Attention: Syndicate Department (Facsimile: (646) 855-3073), with a copy to: ECM Legal (Facsimile: (212) 230-8730) and to J.P. Morgan Securities LLC, 383 Madison Avenue, New York, New York 10179, Attention: Equity Syndicate Desk (Facsimile: (212) 622-8358). Notices to the Company shall be delivered or sent by mail or facsimile transmission to the address of the Company set forth in the Registration Statement, Attention: General Counsel (Fax: (972) 855-3080).

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(c) Governing Law. This Agreement and any claim, controversy or dispute arising under or related to this Agreement shall be governed by and construed in accordance with the laws of the State of New York applicable to agreements made and to be performed in such state.

(d) Counterparts. This Agreement may be signed in counterparts (which may include counterparts delivered by any standard form of telecommunication), each of which shall be an original and all of which together shall constitute one and the same instrument.

(e) Amendments or Waivers. No amendment or waiver of any provision of this Agreement, nor any consent or approval to any departure therefrom, shall in any event be effective unless the same shall be in writing and signed by the parties hereto.

(f) Headings. The headings herein are included for convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement.

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If the foregoing is in accordance with your understanding, please indicate your acceptance of this Agreement by signing in the space provided below.