Exhibit 1.1

EXECUTION VERSION

LAREDO PETROLEUM HOLDINGS, INC.

17,500,000 Shares of Common Stock

Underwriting Agreement

December 14, 2011

J.P. Morgan Securities LLC
Goldman, Sachs & Co.

Merrill Lynch, Pierce, Fenner & Smith

Incorporated

Wells Fargo Securities, LLC

As Representatives of the
several Underwriters listed
in Schedule 1 hereto

c/o J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Ladies and Gentlemen:

Laredo Petroleum Holdings, Inc., a Delaware corporation (“Laredo Holdings”), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representatives (collectively, the “Representatives”), an aggregate of 17,500,000 shares of common stock, par value $0.01 per share (the “Common Stock”), of Laredo Holdings (the “Underwritten Shares”) and, at the option of the Underwriters, up to an additional 2,625,000 shares of Common Stock of Laredo Holdings (the “Option Shares”).  The Underwritten Shares and the Option Shares are herein referred to as the “Shares.”  The shares of Common Stock to be outstanding after giving effect to the sale of the Shares are referred to herein as the “Stock.”

Laredo Holdings is a Delaware corporation that was formed by Laredo Petroleum, LLC, a Delaware limited liability company (“Laredo LLC”) for the purpose of making the proposed issuance and sale of the Shares (the “offering”).  It is understood and agreed to by all parties that concurrently with, or prior to, the closing of this offering, Laredo LLC will complete a corporate reorganization (the “Reorganization”), pursuant to which the following transactions will occur:

A.            Laredo Holdings and Laredo LLC will enter into that certain Agreement and Plan of Merger (the “Merger Agreement”).

B.            Pursuant to the Merger Agreement, Laredo LLC will merge with and into Laredo Holdings, with Laredo Holdings being the surviving entity.

C.            In accordance with the limited liability company agreement of Laredo LLC, (i) all of the outstanding preferred equity units in Laredo LLC will be exchanged for shares of

Common Stock, and (ii) certain series of incentive equity units in Laredo LLC will be exchanged into shares of Common Stock.

D.            In connection with the Reorganization, the certificate of incorporation of Laredo Holdings will be amended and restated (as amended and restated, the “Restated Certificate of Incorporation”) and the bylaws of Laredo Holdings will be amended and restated (as amended and restated, the “Restated Bylaws,” and together with the Merger Agreement and the Restated Certificate of Incorporation, the “Transaction Documents”).

The effective time of the merger is hereinafter referred to as the “Reorganization Effective Time.” As used herein, the “Company” shall mean Laredo LLC and its subsidiaries prior to the Reorganization Effective Time and Laredo Holdings and its subsidiaries after the Reorganization Effective Time.

Prior to the Reorganization Effective Time, Laredo LLC has five wholly-owned subsidiaries: Laredo Holdings, Laredo Petroleum, Inc., a Delaware corporation (“Laredo Petroleum”); Laredo Petroleum Texas, LLC, a Texas limited liability company (“Laredo Texas”); Laredo Gas Services, LLC, a Delaware limited liability company (“Laredo Gas”); and Laredo Petroleum—Dallas, Inc., a Delaware corporation (“Laredo Dallas”).  After the Reorganization Effective Time, Laredo Holdings will have four wholly-owned subsidiaries: Laredo Petroleum, Laredo Texas, Laredo Gas and Laredo Dallas.

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

1.             Registration Statement.  Laredo Holdings 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 (File No. 333-176439), 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 430A 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”; and as used herein, the term “Preliminary Prospectus” means each prospectus included in such registration statement (and any amendments thereto) before effectiveness, any prospectus filed with the Commission pursuant to Rule 424(a) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the prospectus 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 Shares.  If Laredo Holdings has filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement.  Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

At or prior to the Applicable Time (as defined below), Laredo Holdings had prepared the following information (collectively, with the pricing information set forth on Annex B, the

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“Pricing Disclosure Package”):  a Preliminary Prospectus, dated November 28, 2011, filed with the Commission pursuant to Rule 424(a) under the Securities Act and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Annex B hereto.

“Applicable Time” means 5:00 P.M., New York City time, on December 14, 2011.

2.             Purchase of the Shares by the Underwriters.

(a)           Laredo Holdings agrees to issue and sell the Underwritten 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 Laredo Holdings the respective number of Underwritten Shares set forth opposite such Underwriter’s name in Schedule 1 hereto at a price per share (the “Purchase Price”) of $16.0225.  The public offering price of the Shares is not in excess of the price recommended by Goldman, Sachs & Co., acting as qualified independent underwriter within the meaning of FINRA Rule 5121.

In addition, Laredo Holdings agrees to issue and sell the Option Shares to the several Underwriters as provided in this Agreement, and the Underwriters, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from Laredo Holdings the Option Shares at the Purchase Price less an amount per share equal to any dividends or distributions declared by Laredo Holdings and payable on the Underwritten Shares but not payable on the Option Shares.

If any Option Shares are to be purchased, the number of Option Shares to be purchased by each Underwriter shall be the number of Option Shares which bears the same ratio to the aggregate number of Option Shares being purchased as the number of Underwritten Shares set forth opposite the name of such Underwriter in Schedule 1 hereto (or such number increased as set forth in Section 11 hereof) bears to the aggregate number of Underwritten Shares being purchased from Laredo Holdings by the several Underwriters, subject, however, to such adjustments to eliminate any fractional Shares as the Representatives in their sole discretion shall make.

The Underwriters may exercise the option to purchase Option Shares at any time in whole, or from time to time in part, on or before the thirtieth day following the date of the Prospectus, by written notice from the Representatives to Laredo Holdings.  Such notice shall set forth the aggregate number of Option Shares as to which the option is being exercised and the date and time when the Option Shares are to be delivered and paid for, which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date or later than the tenth full business day (as hereinafter defined) after the date of such notice (unless such time and date are postponed in accordance with the provisions of Section 11 hereof).  Any such notice shall be given at least two business days prior to the date and time of delivery specified therein.

(b)           Laredo Holdings 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

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Representatives is advisable, and initially to offer the Shares on the terms set forth in the Prospectus.  Laredo Holdings 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 Laredo Holdings to the Representatives, in the case of the Underwritten Shares, at the offices of Akin Gump Strauss Hauer & Feld LLP, 1111 Louisiana, Suite 4400, Houston, Texas 77002 at 10:00 A.M., New York City time, on December 20, 2011, 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 Laredo Holdings may agree upon in writing or, in the case of the Option Shares, on the date and at the time and place specified by the Representatives in the written notice of the Underwriters’ election to purchase such Option Shares.  The time and date of such payment for the Underwritten Shares is referred to herein as the “Closing Date,” and the time and date for such payment for the Option Shares, if other than the Closing Date, is herein referred to as the “Additional Closing Date.”

Payment for the Shares to be purchased on the Closing Date or any Additional Closing Date, as the case may be, shall be made against delivery to the Representatives for the respective accounts of the several Underwriters of the Shares to be purchased on such date or any Additional Closing Date, as the case may be, with any transfer taxes payable in connection with the sale of such Shares duly paid by Laredo Holdings.  Delivery of the Shares shall be made through the facilities of The Depository Trust Company (“DTC”) unless the Representatives shall otherwise instruct.  The certificates for the Shares will be made available for inspection and packaging by the Representatives at the office of DTC or its designated custodian not later than 1:00 P.M., New York City time, on the business day prior to the Closing Date or any Additional Closing Date, as the case may be.

(d)           Laredo Holdings acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to Laredo Holdings 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, Laredo Holdings or any other person.  Additionally, neither the Representatives nor any other Underwriter is advising Laredo Holdings or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction.  Laredo Holdings 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 Laredo Holdings with respect thereto.  Any review by the Underwriters of Laredo Holdings, 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 Laredo Holdings.

3.             Representations and Warranties of Laredo LLC and Laredo Holdings.Laredo LLC and Laredo Holdings, jointly and severally, represent and warrant to each Underwriter that:

(a)           Preliminary Prospectus.  No order preventing or suspending the use of any Preliminary Prospectus has been issued by the Commission, and each Preliminary Prospectus included in the Pricing Disclosure Package, at the time of filing thereof, complied in all material

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respects with the Securities Act, and no Preliminary Prospectus included in the Pricing Disclosure Package, at the time of filing thereof, contained any untrue statement of a material fact or omitted 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 neither Laredo LLC nor Laredo Holdings makes any representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to either Laredo LLC or Laredo Holdings in writing by such Underwriter through the Representatives expressly for use in any Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(b)           Pricing Disclosure Package.  The Pricing Disclosure Package as of the Applicable Time did not, and as of 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 neither Laredo LLC nor Laredo Holdings makes any representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to Laredo LLC or Laredo Holdings in writing by such Underwriter through the Representatives expressly for use in such Pricing Disclosure Package, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(c)           Issuer Free Writing Prospectus.  Other than the Registration Statement, the Preliminary Prospectus and the Prospectus, neither Laredo LLC nor Laredo Holdings (including its agents and representatives, other than the Underwriters in their capacity as such) has prepared, used, authorized, approved or referred to and neither will prepare, 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 Shares (each such communication by Laredo LLC or Laredo Holdings or its agents and representatives (other than a communication referred to in clause (i) below) 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 or (ii) the documents listed on Annex B hereto, each electronic road show and any other written communications approved in writing in advance by the Representatives.  No such Issuer Free Writing Prospectus conflicts with the information set forth in the Registration Statement.  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 the delivery of, such Issuer Free Writing Prospectus, did not, and as of 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 neither Laredo LLC nor Laredo Holdings makes any representation and warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus or Preliminary Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to Laredo LLC or Laredo Holdings in writing by such Underwriter through the Representatives

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expressly for use in such Issuer Free Writing Prospectus or Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(d)           Registration Statement and Prospectus.  The Registration Statement has been declared effective by the Commission.  No order suspending the effectiveness of the Registration Statement has been issued by the Commission, and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against Laredo Holdings or related to the offering of the Shares has been initiated or threatened by the Commission; as of the applicable effective date of the Registration Statement and any post-effective amendment thereto, the Registration Statement and any such post-effective amendment complied and will comply in all material respects with 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 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 necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that Laredo Holdings makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to Laredo Holdings in writing by such Underwriter through the Representatives expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(e)           Financial Statements.  The historical combined financial statements (including the related notes thereto) of Laredo LLC and its subsidiaries included in the Registration Statement, the Pricing Disclosure Package and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and present fairly in all material respects the financial position of Laredo LLC and its subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; the balance sheet (including the related notes thereto) of Laredo Holdings included in the Registration Statement, the Pricing Disclosure Package and the Prospectus complies in all material respects with the applicable requirements of the Securities Act and presents fairly in all material respects the financial position of Laredo Holdings as of the date indicated; the statement of revenues and direct operating expenses of the interests of Linn Energy Holdings, LLC, Linn Operating, Inc., Mid-Continent I, LLC, Mid-Continent II, LLC, and Linn Exploration Midcontinent, LLC in certain oil and gas properties acquired by Laredo Petroleum (including the related notes thereto) included in the Registration Statement, the Pricing Disclosure Package and the Prospectus complies in all material respects with the applicable requirements of the Securities

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Act and presents fairly in all material respects the results of operations related to such interests for the period specified; all such financial statements have been prepared in conformity with generally accepted accounting principles in the United States applied on a consistent basis throughout the periods covered thereby, and any supporting schedules included in the Registration Statement present fairly in all material respects the information required to be stated therein.  The pro forma financial statements included in the Registration Statement, the Pricing Disclosure Package and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and give effect to assumptions made on a reasonable basis as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus.  The summary historical combined financial data set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the caption “Prospectus summary—Summary historical combined financial data,” and the selected historical combined financial data set forth under the captions “Selected historical combined financial data” in the Registration Statement, the Pricing Disclosure Package and the Prospectus is accurately presented in all material respects and prepared on a basis consistent with the audited historical financial statements and unaudited historical financial statements, as applicable, from which it has been derived.  All disclosures contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus regarding “non-GAAP financial measures” (as such term is defined by the rules and regulations of the Commission) comply in all material respects with Regulation G under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and Item 10 of Regulation S-K of the Securities Act, to the extent applicable.  All other financial information included in the Registration Statement, the Pricing Disclosure Package and the Prospectus has been derived from the accounting records of Laredo LLC and its subsidiaries and presents fairly in all material respects the information shown thereby.

(f)            No Material Adverse Change.  Since the date of the most recent financial statements of Laredo LLC and the date of the most recent balance sheet of Laredo Holdings included in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (i) there has not been any change in the equity capital of Laredo LLC or the capital stock of Laredo Holdings (other than the issuance of shares of Common Stock upon exercise of stock options and warrants described as outstanding in, and the grant of options and awards under existing equity incentive plans described in, the Registration Statement, the Pricing Disclosure Package and the Prospectus), short-term debt or long-term debt of Laredo LLC or any of its subsidiaries, on the one hand, or Laredo Holdings and any of its subsidiaries, on the other hand, 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, stockholders’ equity or results of operations 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 (whether or not in the ordinary course of business) 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 loss or interference with its business that is material to the Company and its subsidiaries taken as a whole and that is either 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 as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(g)           Organization and Good Standing.  Laredo LLC, Laredo Holdings and each of their respective subsidiaries have been duly organized and are validly existing and in good standing under the laws of their respective jurisdictions of organization, are duly qualified to do business and are in good standing in each jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, and

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have all power and authority necessary to own or hold their respective properties and to conduct the businesses in which they are engaged, except where the failure to be so qualified or in good standing or have such power or authority would not, individually or in the aggregate, reasonably be expected to have a material adverse effect on the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole or on the performance by the Company of its obligations under this Agreement (a “Material Adverse Effect”).  After giving effect to the Reorganization, the Company will not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed in Schedule 3 to this Agreement.

(h)           Capitalization.  The Company has an authorized capitalization as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the heading “Capitalization”; except as described in or expressly contemplated by the Pricing Disclosure Package 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 interests of 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 or other equity interests of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock or other equity interests of the Company, as the case may be, conforms in all material respects to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and all the outstanding shares of capital stock or other equity interests of each subsidiary owned, directly or indirectly, by the Company have been duly and validly authorized and issued, are fully paid and non-assessable (except as such nonassessability may be affected by Sections 18-607 and 18-804 of the Delaware LLC Act and Sections 101.206 and 101.613 of the Texas Business Organization Code, as applicable, and limited to the extent set forth in each subsidiary’s organizational documents) and are owned, directly or indirectly, by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party, except as may exist pursuant to that certain Third Amended and Restated Credit Agreement, dated as of July 1, 2011, among Laredo Petroleum, Wells Fargo Bank, N.A., as Administrative Agent, Bank of America, N.A. and JPMorgan Chase Bank, N.A., as Co-Syndication Agents, Societe Generale, Union Bank, N.A. and BMO Harris Financing, Inc., as Co-Documentation Agents, Wells Fargo Securities, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC, as Joint Lead Arrangers and the lenders thereto (the “Credit Agreement”).

(i)            Equity Securities of Laredo LLC.  All of the issued and outstanding equity securities of Laredo LLC have been duly authorized and validly issued in accordance with the Amended and Restated Limited Liability Company Agreement of Laredo LLC (the “LLC Agreement”), and are fully paid (to the extent required by the LLC Agreement) and non-assessable (except as such non-assesssability may be limited by Sections 18-607 and 18-804 of the Delaware Limited Liability Company Act (the “Delaware LLC Act”), and such equity securities are not subject to any pre-emptive or similar rights, which have not been effectively waived or satisfied.

(j)            The Common Stock.  The shares of Common Stock outstanding prior to the issuance of the Shares to be sold by the Company in this offering have been, or after giving

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effect to the Reorganization will be, duly authorized and validly issued, fully paid and nonassessable, and such shares of Common Stock are not subject to any pre-emptive or similar rights, which have not been effectively waived or satisfied.

(k)           The Shares.  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 nonassessable and will conform 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.

(l)            Stock Options.  With respect to the stock options (the “Stock Options”) granted pursuant to the stock-based compensation plans of the Company and its subsidiaries (the “Company Stock Plans”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Internal Revenue Code of 1986, as amended (the “Code”) was granted in accordance with the requirements of Section 422 of the Code, (ii) each grant of a Stock Option was duly authorized no later than the date on which the grant of such Stock Option was by its terms to be effective (the “Grant Date”) by all necessary corporate action, including, as applicable, approval by the board of directors of the Company (or a duly constituted and authorized committee thereof) and any required stockholder approval by the necessary number of votes or written consents, and the award agreement governing such grant (if any) was duly executed and delivered by each party thereto, (iii) each such grant was made in accordance with the terms of the Company Stock Plans, the Exchange Act and all other applicable laws and regulatory rules or requirements, and (iv) each such grant was properly accounted for in accordance with GAAP in the financial statements (including the related notes) of the Company.

(m)          Due Authorization.  Each of Laredo LLC and Laredo Holdings has full right, power and authority to execute and deliver this Agreement and each of the Transaction Documents to which it is a party and to perform its obligations hereunder and thereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of this Agreement and each of the Transaction Documents to which it is a party and the consummation by it of the transactions contemplated hereby and thereby has been duly and validly taken.

(n)           Underwriting Agreement.  This Agreement has been duly authorized, executed and delivered by each of Laredo LLC and Laredo Holdings.

(o)           Transaction Documents.  Each Transaction Document to which Laredo LLC and Laredo Holdings, as applicable, are a party has been duly authorized by Laredo LLC and Laredo Holdings, as applicable, and, 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 each of Laredo LLC and Laredo Holdings, as applicable, enforceable against each of them in accordance with its terms, except as enforceability may be limited by applicable bankruptcy, insolvency or similar laws affecting creditors’ rights generally or by equitable principles relating to enforceability.

(p)           No Violation or Default.  Neither Laredo LLC, Laredo Holdings nor any of their respective subsidiaries is (i) in violation of its charter or by-laws or similar organizational

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documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which Laredo LLC, Laredo Holdings or any of their respective subsidiaries is a party or by which Laredo LLC, Laredo Holdings or any of their respective subsidiaries is bound or to which any of the property or assets of Laredo LLC, Laredo Holdings or any of their respective subsidiaries is subject; 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, in the case of clauses (ii) and (iii) above, for any such default or violation that would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(q)           No Conflicts.  The execution, delivery and performance by Laredo LLC and Laredo Holdings of each of the Transaction Documents, the issuance and sale of the Shares and the consummation of the transactions contemplated by the Transaction Documents, including the Reorganization, will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of Laredo LLC, Laredo Holdings or any of their respective subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which Laredo LLC, Laredo Holdings or any of their respective subsidiaries is a party or by which Laredo LLC, Laredo Holdings or any of their respective subsidiaries is bound or to which any of the property or assets of Laredo LLC, Laredo Holdings or any of their respective subsidiaries is subject, (ii) result in any violation of the provisions of the charter or by-laws or similar organizational documents of Laredo LLC, Laredo Holdings or any of their respective subsidiaries or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (i) and (iii) above, for any such conflict, breach, violation, default, lien, charge or encumbrance that has been consented to or waived in writing prior to the date hereof or would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect or materially impair the ability of Laredo LLC or Laredo Holdings to consummate the Reorganization or any other transactions provided for in this Agreement.

(r)            No Consents Required.  No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by Laredo LLC or Laredo Holdings of each of the Transaction Documents, the issuance and sale of the Shares and the consummation of the transactions contemplated by the Transaction Documents, including the Reorganization, except for (i) the registration of the Shares under the Securities Act, (ii) such consents, approvals, authorizations, orders and registrations or qualifications as may be required by FINRA and under applicable state securities laws in connection with the purchase and distribution of the Shares by the Underwriters, (iii) consents that have been, or prior to the Closing Date will be, obtained, and (iv) consents that, if not obtained, would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect or materially impair the ability of the Company to consummate the transactions contemplated herein or to consummate the Reorganization.

(s)           Consents Necessary to Effect the Reorganization.  Each of Laredo LLC and Laredo Holdings have received, or will receive prior to the Reorganization Effective Time, all

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consents, approvals and authorizations necessary to effect the Reorganization under its organizational documents, the Delaware LLC Act or the Delaware General Corporation Law, as applicable and the Credit Agreement, other than such consents, approvals and authorizations that, if not obtained, would not reasonably be expected, individually or in the aggregate, to materially impair the ability of the Company to consummate the transactions contemplated herein or to consummate the Reorganization.

(t)            Legal Proceedings.  Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no legal, governmental or regulatory investigations, actions, suits or proceedings pending to which Laredo LLC, Laredo Holdings or any of their respective subsidiaries is a party or to which any property of Laredo LLC, Laredo Holdings or any of their respective subsidiaries is the subject that, individually or in the aggregate, if determined adversely to Laredo LLC, Laredo Holdings or any of their respective subsidiaries, could reasonably be expected to have a Material Adverse Effect; to the knowledge of Laredo LLC and Laredo Holdings, no such investigations, actions, suits or proceedings are threatened or contemplated by any governmental or regulatory authority or threatened by others; and (i) there are no current or pending legal, governmental or regulatory actions, suits or proceedings that are required under the Securities Act to be described in the Registration Statement, the Pricing Disclosure Package or the Prospectus that are not so described in the Registration Statement, the Pricing Disclosure Package and the Prospectus and (ii) there are no statutes, regulations or contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement or described in the Registration Statement, the Pricing Disclosure Package or the Prospectus that are not so filed as exhibits to the Registration Statement or described in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(u)           Independent Accountants.  Grant Thornton LLP, who has certified certain financial statements of Laredo LLC, Laredo Holdings and their respective subsidiaries, is an independent registered public accounting firm with respect to Laredo LLC, Laredo Holdings and their respective 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.

(v)           Independent Reserve Engineers.  Ryder Scott Company, L.P. (“Ryder Scott”), who has prepared the reserve reports and estimates of proved reserves disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, has represented to Laredo LLC and Laredo Holdings that they are, and Laredo LLC and Laredo Holdings believe them to be, independent reserve engineers with respect to Laredo LLC, Laredo Holdings and their respective subsidiaries within the applicable rules and regulations adopted by the Commission and as required by the Securities Act for the periods set forth in the Preliminary Prospectus and the Prospectus.

(w)          Information Underlying Reserve Reports.  The oil and natural gas proved reserve estimates of the Company and its subsidiaries contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus are derived from reports that have been prepared by Ryder Scott, and such estimates fairly reflect, in all material respects, the oil and natural gas reserves attributable to the Company and its subsidiaries at the dates indicated therein and are

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prepared in accordance, in all material respects, with Commission guidelines applied on a consistent basis throughout the periods involved.

(x)            Title to Real and Personal Property.  The Company and its subsidiaries have good and marketable title in fee simple (in the case of real property) to, or have valid and marketable rights to lease or otherwise use, all items of real and personal property that are material to the respective businesses of the Company and its subsidiaries, in each case free and clear of all liens, encumbrances, claims and defects of title except those that (i) do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries, (ii) could not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect or (iii) exist pursuant to the Credit Agreement.

(y)           Title to Oil and Gas Properties.  Each of the Company and its subsidiaries has good and defensible title to all of its oil and gas properties in each case free and clear of all liens, encumbrances and defects, except (i) such as are described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (ii) such as are permitted under the Credit Agreement, or (iii) such as do not materially affect the value of the properties and do not materially interfere with the use of the properties of the Company and its subsidiaries taken as a whole; and all of the leases and subleases under which the Company or any of its subsidiaries holds or uses properties described in the Registration Statement, the Pricing Disclosure Package and the Prospectus are in full force and effect, with such exceptions as would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect, and neither the Company nor any of its subsidiaries has any notice of any material claim of any sort that has been asserted by anyone adverse to the rights of the Company or its subsidiaries under any of the leases or subleases mentioned above, or affecting or questioning the rights of the Company or any subsidiary thereof to the continued possession or use of the leased or subleased premises, except for such claims that, if successfully asserted, would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect; provided however, that the enforceability of such leases and subleases, as the case may be, may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and by general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law).

(z)            Rights-of-Way.  The Company and its subsidiaries have such consents, easements, rights-of-way or licenses from any person (“rights-of-way”) as are necessary to enable the Company and its subsidiaries to conduct their respective businesses in the manner described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, except for such rights-of-way the failure of which to obtain would not reasonably be expected, individually or in the aggregate, to result in a Material Adverse Effect.  The rights-of-way owned by Company and its subsidiaries are subject only to such qualifications, reservations and encumbrances as may be set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus or as would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(aa)         Title to Intellectual Property.  The Company and its subsidiaries own or possess adequate rights to use all material patents, patent applications, trademarks, service marks, trade names, trademark registrations, service mark registrations, copyrights, licenses and know-how

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(including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures) necessary for the conduct of their respective businesses as currently conducted and as proposed to be conducted, and the conduct of their respective businesses will not conflict in any material respect with any such rights of others.  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company and its subsidiaries have not received any notice of infringement of or conflict with the asserted rights of others with respect to any of the foregoing, which if the subject of an unfavorable decision or ruling, would reasonably be expected, individually or in the aggregate, to result in a Material Adverse Effect.

(bb)         No Undisclosed Relationships.  No relationship, direct or indirect, exists between or among Laredo LLC, Laredo Holdings or any of their respective subsidiaries, on the one hand, and the directors, officers, stockholders, customers or suppliers of Laredo LLC, Laredo Holdings or any of their respective subsidiaries, on the other, that is required by the Securities Act to be described in the Registration Statement and the Prospectus and that is not so described in such documents and in the Pricing Disclosure Package.

(cc)         Investment Company Act.  Neither Laredo LLC nor Laredo Holdings is and, after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, Laredo Holdings will not be required to register as an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Investment Company Act”).

(dd)         Taxes.  Laredo LLC, Laredo Holdings and their respective subsidiaries have paid all federal, state, local and foreign taxes and filed all tax returns required to be paid or filed through the date hereof, except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and except as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there is no material tax deficiency that has been, or could reasonably be expected to be, asserted against Laredo LLC, Laredo Holdings or any of their respective subsidiaries or any of their respective properties or assets.

(ee)         Licenses and Permits.  The Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, except where the failure to possess or make the same would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such license, certificate, permit or authorization.

(ff)           No Labor Disputes.  No labor disturbance by or dispute with employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is contemplated or threatened, and the Company is not aware of any existing or imminent labor disturbance by, or

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dispute with, the employees of any of its or its subsidiaries’ principal suppliers, contractors or customers, except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(gg)         Compliance with and Liability under Environmental Laws.  (i) The Company and its subsidiaries (a) are, and at all prior times were, in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, requirements, decisions, judgments, decrees, orders and the common law relating to pollution or the protection of the environment, natural resources or human health or safety, including those relating to the generation, storage, treatment, use, handling, transportation, Release or threat of Release of Hazardous Materials (collectively, “Environmental Laws”), (b) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under applicable Environmental Laws to conduct their respective businesses, (c) have not received written notice of any actual or potential liability under or relating to, or actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any Release or threat of Release of Hazardous Materials, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, (d) are not conducting or paying for, in whole or in part, any investigation, remediation or other corrective action pursuant to any Environmental Law at any location, and (e) are not a party to any order, decree or agreement that imposes any obligation or liability under any Environmental Law, and (ii) there are no costs or liabilities associated with Environmental Laws of or relating to the Company or its subsidiaries, except in the case of each of (i) and (ii) above, for any such failure to comply, or failure to receive required permits, licenses, certificates or approvals, or cost or liability, as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and (iii) except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (a) there are no proceedings that are pending, or that are known to be contemplated, against the Company or any of its subsidiaries under any Environmental Laws in which a governmental entity is also a party, other than such proceedings regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed, (b) the Company and its subsidiaries are not aware of any facts or issues regarding compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws, including the Release or threat of Release of Hazardous Materials, that could reasonably be expected to have a Material Adverse Effect, and (c) none of the Company and its subsidiaries anticipates material capital expenditures relating to any Environmental Laws.

(hh)         Hazardous Materials.  There has been no storage, generation, transportation, use, handling, treatment, Release or threat of Release of Hazardous Materials by, relating to or caused by the Company or any of its subsidiaries (or, to the knowledge of the Company and its subsidiaries, any other entity (including any predecessor) for whose acts or omissions the Company or any of its subsidiaries is or could reasonably be expected to be liable) at, on, under or from any property or facility now or previously owned, operated or leased by the Company or any of its subsidiaries, or at, on, under or from any other property or facility, in violation of any Environmental Laws or in a manner or amount or to a location that could reasonably be expected to result in any liability under any Environmental Law, except for any violation or liability which would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.  “Hazardous Materials” means any material, chemical, substance, waste, pollutant, contaminant, compound, mixture, or constituent thereof, in any form or amount, including

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petroleum (including crude oil or any fraction thereof) and petroleum products, natural gas liquids, asbestos and asbestos containing materials, naturally occurring radioactive materials and brine, which can give rise to liability under any Environmental Law.  “Release” means any spilling, leaking, seepage, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, disposing, depositing, dispersing, or migrating in, into or through the environment, or in, into from or through any building or structure.

(ii)           Compliance with ERISA.  (i) Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income 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 of the Code) would have any liability (each, a “Plan”) has been maintained in compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Code, except for noncompliance that has not resulted in or could not reasonably be expected to result in material liability to the Company or its subsidiaries; (ii) no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any Plan, excluding transactions effected pursuant to a statutory or administrative exemption, that has resulted in or could reasonably be expected to result in material liability to the Company or its subsidiaries; (iii) for each Plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, the minimum funding standard of Section 412 of the Code or Section 302 of ERISA, as applicable, has been satisfied (without taking into account any waiver thereof or extension of any amortization period) and is reasonably expected to be satisfied in the future (without taking into account any waiver thereof or extension of any amortization period); (iv) except as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the fair market value of the assets of each Plan that is required to be funded by applicable law exceeds the present value of all benefits accrued under such Plan (determined based on those assumptions used to fund such Plan); (v) no “reportable event” (within the meaning of Section 4043(c) of ERISA) has occurred or is reasonably expected to occur that either has resulted, or could reasonably be expected to result, in material liability to the Company or its subsidiaries; and (vi) neither the Company nor any member of the Controlled Group has incurred, nor reasonably expects to incur, any liability under Title IV of ERISA (other than contributions to the Plan or premiums to the PBGC, in the ordinary course and without default) in respect of a Plan (including a “multiemployer plan,” within the meaning of Section 4001(a)(3) of ERISA).

(jj)           Disclosure Controls.  The Company and its subsidiaries maintain an effective system of “disclosure controls and procedures” (to the extent required by and as such term is defined in Rule 13a-15(e) of the Exchange Act) that has been designed to ensure that information required to be disclosed by the Company in reports that it files or submits under the Exchange Act, as applicable, 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.

(kk)         Accounting Controls.  The Company and its subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in

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accordance with generally accepted accounting principles, including policies and procedures that 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 Pricing Disclosure Package and the Prospectus, there are no material weaknesses in the Company’s internal controls.  The Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of:  (x) all significant deficiencies and material weaknesses in the design or operation of internal controls over financial reporting which have adversely affected or are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information; and (y) any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting.

(ll)           Insurance.  The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, which insurance is in amounts and insures against such losses and risks as are reasonably adequate to protect them and their businesses in a manner consistent with other businesses similarly situated; and neither the Company nor any of its subsidiaries has (i) received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance or (ii) any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage at reasonable cost from similar insurers as may be necessary to continue its business.

(mm)       No Unlawful Payments.  Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate 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.

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

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(oo)         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, 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 for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(pp)         No Restrictions on Subsidiaries.  No subsidiary of the Company is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s properties or assets to the Company or any other subsidiary of the Company, except for such prohibitions as exist pursuant to the Credit Agreement or the indenture filed as an exhibit to the Registration Statement or as are otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(qq)         No Broker’s Fees.  None of Laredo LLC, Laredo Holdings or any of their respective subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against Laredo LLC, Laredo Holdings or any of their respective subsidiaries or any Underwriter for a brokerage commission, finder’s fee or like payment to any person other than the Underwriters and their affiliates in connection with the offering and sale of the Shares.

(rr)           No Registration Rights.  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, no person has the right to require Laredo LLC, Laredo Holdings or any of their respective subsidiaries to register any securities for sale under the Securities Act by reason of the filing of the Registration Statement with the Commission or the issuance and sale of the Shares.

(ss)         No Stabilization.  Neither Laredo LLC nor Laredo Holdings has 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 Shares.

(tt)           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 Pricing Disclosure Package or the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(uu)         Statistical and Market Data.  Nothing has come to the attention of Laredo LLC or Laredo Holdings that has caused Laredo LLC or Laredo Holdings to believe that the statistical and market-related data included in the Registration Statement, the Pricing Disclosure Package and the Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

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(vv)         Sarbanes-Oxley Act.  To the extent applicable to the Company on the date hereof, there is and has been no failure on the part of the Company or, to the knowledge of the Company, any of the Company’s directors or officers, in their capacities as such, to comply 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.

(ww)       Status under the Securities Act.  At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that Laredo Holdings or any offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Shares and at the date hereof, Laredo Holdings was not and is not an “ineligible issuer,” as defined in Rule 405 under the Securities Act.

(xx)          Corporate Reorganization.  As of the Closing Date, Laredo LLC and Laredo Holdings will have filed all notices, reports, documents or other information required to be filed pursuant to, and will have otherwise complied with all requirements of, all applicable laws in connection with the consummation of the Reorganization, except in each case where such failure would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect.

4.             Further Agreements of Laredo Holdings.  Laredo Holdings covenants and agrees with each Underwriter that:

(a)           Required Filings.  Laredo Holdings will file the final Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430A under the Securities Act, will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; and 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 second business day succeeding the date of this Agreement in such quantities as the Representatives may reasonably request.

(b)           Delivery of Copies.  Laredo Holdings will deliver, without charge, (i) to the Representatives, four signed copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith; and (ii) to each Underwriter (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto (without exhibits) and (B) during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto and each Issuer Free Writing Prospectus) 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 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.  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

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Prospectus, Laredo Holdings 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 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 objects.

(d)           Notice to the Representatives.  Laredo Holdings will advise the Representatives promptly (i) when the Registration Statement has become effective; (ii) when any amendment to the Registration Statement has been filed or becomes effective; (iii) when any supplement to the Prospectus or any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed; (iv) 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; (v) 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; (vi) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, 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 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; and (vii) of the receipt by Laredo Holdings of any notice with respect to any suspension of the qualification of the Shares for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and Laredo Holdings 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 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 law, Laredo Holdings 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 to such dealers as the 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 law and (2) if at any time prior to the Closing Date (i) any event 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

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misleading or (ii) it is necessary to amend or supplement the Pricing Disclosure Package to comply with law, Laredo Holdings 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 to such dealers as the Representatives may designate such amendments or supplements to the Pricing Disclosure Package 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.  Laredo Holdings will qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Representatives shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Shares; provided that Laredo Holdings 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)           Earnings Statement.  Laredo Holdings will make generally available to its security holders and the Representatives as soon as practicable an earnings 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 Laredo Holdings occurring after the “effective date” (as defined in Rule 158) of the Registration Statement.

(h)           Clear Market.  For a period of 180 days after the date of the Prospectus, Laredo Holdings, its officers and directors or certain affiliates of Laredo Holdings, each as listed on Schedule 2 hereto (each, a “Lock-Up Party”), 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 (including, without limitation, Stock or such other securities which may be deemed to be beneficially owned by each such Lock-Up Party in accordance with the rules and regulations of the Commission and securities which may be issued upon exercise of a stock option or warrant), or publicly disclose the intention to make any offer, sale, pledge, disposition or filing (other than filings on Form S-8 relating to the Company Stock Plans), 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, or (iii) make any demand for or exercise any right with respect to the registration of any shares of Sock or any security convertible into or exercisable or exchangeable for Stock, without the prior written consent of J.P. Morgan Securities LLC, Goldman, Sachs & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, other than the Shares to be sold hereunder and any shares of Stock issued for awards or upon the exercise of options granted under Company Stock Plans, except that Warburg Pincus, LLC will be permitted to spin-off our Stock that it owns to its shareholders

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180 days after the date of the Prospectus, subject to certain restrictions.  Notwithstanding the foregoing, if (1) during the last 17 days of the 180-day restricted period, Laredo Holdings issues an earnings release or announces material news or a material event relating to Laredo Holdings occurs; or (2) prior to the expiration of the 180-day restricted period, Laredo Holdings announces that it will release earnings results during the 16-day period beginning on the last day of the 180-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, announcement of the material news or occurrence of the material event.

If J.P. Morgan Securities LLC, Goldman, Sachs & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, in their sole discretion, agree to release or waive the restrictions set forth in a lock-up letter described in Section 6(n) hereof for a Lock-Up Party and provide Laredo Holdings with notice of the impending release or waiver at least three business days before the effective date of the release or waiver, Laredo Holdings agrees to announce the impending release or waiver by a press release substantially in the form of Exhibit B hereto through a major news service at least two business days before the effective date of the release or waiver.

(i)            Use of Proceeds.  Laredo Holdings 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.”

(j)            No Stabilization.  Laredo Holdings 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.

(k)           Exchange Listing.  Laredo Holdings will use its best efforts to list, subject to notice of issuance, the Shares on the New York Stock Exchange (the “Exchange”).

(l)            Reports.  For a period of two years from the date of this Agreement, so long as the Shares are outstanding, Laredo Holdings will furnish to the Representatives, 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 Laredo Holdings will be deemed to have furnished such reports and financial statements to the Representatives to the extent they are filed on the Commission’s Electronic Data Gathering, Analysis, and Retrieval system.

(m)          Record Retention.  Laredo Holdings will, pursuant to reasonable procedures developed in good faith, retain copies of each Issuer Free Writing Prospectus that is not filed with the Commission in accordance with Rule 433 under the Securities Act.

(n)           Filings.  Laredo Holdings will file with the Commission such reports as may be required by Rule 463 under the Securities Act.

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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 Laredo Holdings and not incorporated by reference into the Registration Statement and any press release issued by Laredo Holdings) 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 B or permitted pursuant to Section 3(c) or Section 4(c) above (including any electronic road show approved in advance by Laredo Holdings), or (iii) any free writing prospectus prepared by such underwriter and approved by Laredo Holdings in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”).

(b)           It has not and will not, without the prior written consent of Laredo Holdings, use any free writing prospectus that contains the final terms of the Shares unless such terms have previously been included in a free writing prospectus filed with the Commission.

(c)           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 Underwritten Shares on the Closing Date or the Option Shares on the Additional Closing Date, as the case may be, as provided herein is subject to the performance by Laredo Holdings 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 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 Representatives.

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

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(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 or preferred stock of, or guaranteed by, the Laredo LLC, Laredo Holdings or any of their respective subsidiaries that are rated by a “nationally recognized statistical rating organization,” as such term is defined in Section 3(a)(62) of the Exchange Act, (i) no downgrading shall have occurred in the rating accorded any such debt securities or preferred stock and (ii) no such organization shall have publicly announced that it has under surveillance or review, or has changed its outlook with respect to, its rating of any such debt securities or preferred stock (other than an announcement with positive implications of a possible upgrading).

(d)           No Material Adverse Change.  No event or condition of a type described in Section 3(f) hereof shall have occurred or shall exist, which event or condition is not described in the Pricing Disclosure Package (excluding any amendment or supplement thereto) and the Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the Representatives makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or any Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus.

(e)           Officer’s Certificate.  The Representatives shall have received on and as of the Closing Date or any Additional Closing Date, as the case may be, a certificate of the chief financial officer or chief accounting officer of Laredo Holdings and one additional senior executive officer of Laredo Holdings who is satisfactory to the Representatives (i) confirming that such officers have carefully reviewed the Registration Statement, the Pricing Disclosure Package and the Prospectus and, to the knowledge of such officers, the representations set forth in Sections 3(b) and 3(d) hereof are true and correct, (ii) confirming that the other representations and warranties of Laredo LLC and Laredo Holdings in this Agreement are true and correct and that Laredo Holdings has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date or any Additional Closing Date, as the case may be, and (iii) to the effect set forth in paragraphs (a), (c) and (d) above.

(f)            Auditor Comfort Letters.  On the date of this Agreement and on the Closing Date or any Additional Closing Date, as the case may be, Grant Thornton LLP shall have furnished to the Representatives, at the request of Laredo Holdings, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, 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 in the Registration Statement, the Pricing Disclosure Package and the Prospectus; provided, that the letter delivered on the Closing Date or any Additional Closing Date, as the case may be, shall use a “cut-off” date no more than three business days prior to such Closing Date or such Additional Closing Date, as the case may be.

(g)           Reserve Engineer Confirmation Letters. On the date of this Agreement and on the Closing Date or any Additional Closing Date, as the case may be, Ryder Scott shall have furnished to the Representatives, at the request of Laredo Holdings, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably

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satisfactory to the Representatives, containing statements and information of the type customarily included in reserve engineers’ “confirmation letters” to underwriters with respect to the reserve reports, estimates of proved reserves and other reserve information contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(h)           Opinion and 10b-5 Statement of Counsel for Laredo Holdings. Akin Gump Strauss Hauer & Feld L.L.P., counsel for Laredo Holdings, shall have furnished to the Representatives, at the request of Laredo Holdings, their written opinion and 10b-5 statement, dated the Closing Date or any Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, to the effect set forth in Annex A-1 hereto.

(i)            Opinion of General Counsel for Laredo Holdings. Kenneth E. Dornblaser, General Counsel of Laredo Holdings, shall have furnished to the Representatives, a written opinion, dated the Closing Date or any Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, to the effect set forth in Annex A-2 hereto.

(j)            Opinion and 10b-5 Statement of Counsel for the Underwriters.  The Representatives shall have received on and as of the Closing Date or any Additional Closing Date, as the case may be, an opinion and 10b-5 statement of Andrews Kurth LLP, counsel for the Underwriters, with respect to such matters as the Representatives 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 or any Additional Closing Date, as the case may be, 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 or any Additional Closing Date, as the case may be, prevent the issuance or sale of the Shares.

(l)            Good Standing.  The Representatives shall have received on and as of the Closing Date or any Additional Closing Date, as the case may be, satisfactory evidence of the good standing of Laredo Holdings and its subsidiaries in their respective jurisdictions of organization and their good standing as foreign entities in such other jurisdictions as the Representatives 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 or Additional Closing Date, as the case may be, shall have been approved for listing on the Exchange, subject to official notice of issuance.

(n)           Lock-up Agreements.  The “lock-up” agreements, each substantially in the form of Exhibit A hereto, between you and each of the Lock-Up Parties relating to sales and certain other dispositions of shares of Stock or certain other securities, delivered to you on or before the date

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hereof, shall be full force and effect on the Closing Date or Additional Closing Date, as the case may be.

(o)           Corporate Reorganization.  The Reorganization, as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, shall have been consummated in the manner described therein.

(p)           Additional Documents.  On or prior to the Closing Date or any Additional Closing Date, as the case may be, Laredo Holdings shall have furnished to the Representatives such further certificates and documents as the Representatives 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.

7.             Indemnification and Contribution.

(a)           Indemnification of the Underwriters.  Laredo Holdings agrees to indemnify and hold harmless each Underwriter, its affiliates, directors and officers 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, 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 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 Laredo Holdings in writing by such Underwriter through the Representatives 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 Laredo Holdings.  Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless Laredo Holdings, its directors, its officers who signed the Registration Statement and each person, if any, who controls Laredo Holdings 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

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information relating to such Underwriter furnished to Laredo Holdings in writing by such Underwriter through the Representatives expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus, 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 furnished on behalf of each Underwriter and set forth under the caption “Underwriting” in the Prospectus: (i) the names of the Underwriters in the table set forth in the first paragraph, (ii) the amount of the selling concession set forth in the third paragraph and (iii) the statements regarding stabilizing transactions set forth in the thirteenth and fourteenth paragraphs.

(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 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 interests 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; provided, however, that if indemnity may be sought pursuant to Section 8 hereof in respect of such proceeding, then in addition to such separate firm of the Underwriters, their affiliates and such control persons of the Underwriters the Indemnifying Person shall be liable for the fees and expenses of not more than one separate firm (in addition to any local counsel) for Goldman, Sachs & Co., in its capacity as QIU, and the affiliates, directors, officers and each person, if any, who controls Goldman, Sachs & Co. within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act.  Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of

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such Underwriter shall be designated in writing by the Representatives and any such separate firm for Laredo Holdings, its directors, its officers who signed the Registration Statement and any control persons of Laredo Holdings shall be designated in writing by Laredo Holdings.  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.  Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement.  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 Laredo Holdings, 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 Laredo Holdings, 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 Laredo Holdings, 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 Laredo Holdings 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 Laredo Holdings, 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 Laredo Holdings or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e)           Limitation on Liability.  Laredo Holdings and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 7 were determined by pro rata

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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 this Section 7, 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 this Section 7 are several in proportion to their respective purchase obligations hereunder and not joint.

(f)            Non-Exclusive Remedies.  The remedies provided for in 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.             Indemnification of QIU.

(a)           Laredo Holdings hereby confirms its engagement of Goldman, Sachs & Co. as, and Goldman, Sachs & Co. hereby confirms its agreement with Laredo Holdings to render services as, a “qualified independent underwriter” within the meaning of Financial Industry Regulatory Authority, Inc. (“FINRA”) Rule 5121(f)(12) with respect to the offering and sale of the Shares.  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, Laredo Holdings agrees to pay the QIU $10,000 on the Closing Date (as defined herein).

(b)           Laredo Holdings will indemnify and hold harmless Goldman, Sachs & Co., in its capacity as QIU, against any losses, claims, damages or liabilities, joint or several, to which the QIU may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon (i) an untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, the Registration Statement or the Prospectus, or any amendment or supplement thereto, (ii) the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading or (iii) any act or omission to act or any alleged act or omission to act by Goldman, Sachs & Co. as QIU in connection with any transaction contemplated by this Agreement or undertaken in preparing for the purchase, sale and delivery of the Shares, except with respect to clauses (i) and (ii) for any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information furnished to Laredo Holdings in writing by Goldman, Sachs & Co., in its capacity as QIU, for use therein, and with respect to clause (iii) to the extent that any such loss, claim, damage or liability results from the gross negligence or bad faith of Goldman, Sachs & Co. in performing the services as QIU, and will reimburse the QIU for any legal or other

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expenses reasonably incurred by the QIU in connection with investigating or defending any such action or claim as such expenses are incurred.

(c)           If the indemnification provided for in this Section 8 is unavailable to or insufficient to hold harmless Goldman, Sachs & Co., in its capacity as QIU, under subsection (b) of this Section 8 in respect of any losses, claims, damages or liabilities (or actions in respect thereof) referred to therein, then Laredo Holdings shall contribute to the amount paid or payable by the QIU as a result of such losses, claims, damages or liabilities (or actions in respect thereof) in such proportion as is appropriate to reflect the relative benefits received by Laredo Holdings on the one hand and the QIU on the other from the offering of the Shares.  If, however, the allocation provided by the immediately preceding sentence is not permitted by applicable law or if the QIU failed to give the notice required under Section 7(c), then Laredo Holdings shall contribute to such amount paid or payable by the QIU in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of Laredo Holdings on the one hand and the QIU on the other in connection with the statements or omissions which resulted in such losses, claims, damages or liabilities (or actions in respect thereof), as well as any other relevant equitable considerations.  The relative benefits received by Laredo Holdings on the one hand and the QIU on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by Laredo Holdings, as set forth in the table on the cover page of the Prospectus, bear to the fees payable to the QIU pursuant to this Agreement.  The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by Laredo Holdings on the one hand or the QIU on the other and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.  Laredo Holdings and the QIU agree that it would not be just and equitable if contributions pursuant to this subsection (c) were determined by pro rata allocation or by any other method of allocation which does not take account of the equitable considerations referred to above in this subsection (c).  The amount paid or payable by the QIU as a result of the losses, claims, damages or liabilities (or actions in respect thereof) referred to above in this subsection (c) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim.  No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

(d)           The obligations of Laredo Holdings under this Section 8 shall be in addition to any liability which Laredo Holdings may otherwise have and shall extend, upon the same terms and conditions, to each person, if any, who controls the QIU within the meaning of the Act.

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

10.           Termination.  This Agreement may be terminated in the absolute discretion of the Representatives, by notice to Laredo LLC and Laredo Holdings, if after the execution and delivery of this Agreement and prior to the Closing Date or, in the case of the Option Shares, prior to the Additional Closing Date (i) trading generally shall have been suspended or materially limited on or by any of the Exchange, the American Stock Exchange, the Nasdaq Stock Market,

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the Chicago Board Options Exchange, the Chicago Mercantile Exchange or the Chicago Board of Trade; (ii) trading of any securities issued or guaranteed by the Company shall have been suspended on any exchange or in any over-the-counter market; (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York State authorities or a material disruption in securities settlement or clearance services in the United States shall have occurred or (iv) there shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, in the judgment of the Representatives, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or any Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus.

11.           Defaulting Underwriter.

(a)           If, on the Closing Date or any Additional Closing Date, as the case may be, 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 Laredo Holdings on the terms contained in this Agreement.  If, within 36 hours after any such default by any Underwriter, the non-defaulting Underwriters do not arrange for the purchase of such Shares, then Laredo Holdings 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 Laredo Holdings may postpone the Closing Date or any Additional Closing Date, as the case may be, for up to five full business days in order to effect any changes that in the opinion of counsel for Laredo Holdings or counsel for the Underwriters may be necessary in the Registration Statement and the Prospectus or in any other document or arrangement, and Laredo Holdings 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 1 hereto that, pursuant to this Section 11, 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 Laredo Holdings as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date or any Additional Closing Date, as the case may be, does not exceed one-eleventh of the aggregate number of Shares to be purchased on such date, then Laredo Holdings 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 Laredo Holdings as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on

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the Closing Date or any Additional Closing Date, as the case may be, exceeds one-eleventh of the aggregate amount of Shares to be purchased on such date, or if Laredo Holdings shall not exercise the right described in paragraph (b) above, then this Agreement or, with respect to any Additional Closing Date, the obligation of the Underwriters to purchase Shares on the Additional Closing Date shall terminate without liability on the part of the non-defaulting Underwriters.  Any termination of this Agreement pursuant to this Section 11 shall be without liability on the part of Laredo Holdings, except that Laredo Holdings will continue to be liable for the payment of expenses as set forth in Section 12 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 Laredo Holdings or any non-defaulting Underwriter for damages caused by its default.

12.           Payment of Expenses.

(a)           Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, Laredo Holdings will pay or cause to be paid 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 Laredo Holdings’ counsel and independent accountants; (iv) the fees and expenses incurred in connection with the registration or qualification of the Shares under the state or foreign securities or blue sky laws of such jurisdictions as the Representatives may reasonably 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, including reasonable fees and expenses of Underwriters’ counsel in an amount not to exceed $15,000; (viii) all costs and expenses of the Company’s officers and employees and any other expenses of the Company relating to any investor or “road show” presentations in connection with the offering and sale of the Shares, including, without limitation, any travel expenses of the Company’s officers and employees and any other expenses of the Company, provided it is expressly agreed that the Company and the Underwriters will each pay 50% of the costs of any chartered aircraft used by the Underwriters and the Company in connection with any such meetings with investors; and (ix) all expenses and application fees related to the listing of the Shares on the Exchange.

(b)           If (i) this Agreement is terminated pursuant to Section 10, (ii) Laredo Holdings 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, Laredo Holdings agrees to reimburse the Underwriters for all out-of-pocket costs and expenses (including the fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

31

13.           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.

14.           Survival.

The respective indemnities, rights of contribution, representations, warranties and agreements of Laredo LLC and Laredo Holdings and the Underwriters contained in this Agreement or made by or on behalf of Laredo LLC and Laredo Holdings 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 Laredo Holdings or the Underwriters.

15.           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.

16.           Miscellaneous.

(a)           Authority of the Representatives.  Any action by the Underwriters hereunder may be taken by the Representatives on behalf of the Underwriters, and any such action taken by the Representatives shall be binding upon the Underwriters.

(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 the Representatives c/o J.P. Morgan Securities LLC, 383 Madison Avenue, New York, New York 10179 (fax: (212) 622-8358), Attention: Equity Syndicate Desk; Goldman, Sachs & Co., 200 West Street, New York, New York, 10282, Attention: Registration Department; and Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, Attention: Syndicate Department, with a copy to ECM Legal.  Notices to Laredo LLC and Laredo Holdings shall be given to it at 15 W. Sixth Street, Suite 1800, Tulsa, Oklahoma 74119, (fax: (918) 513-4571); Attention:  Mark Womble.

(c)           Patriot Act Compliance.  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 Laredo LLC and Laredo Holdings, which information may include the name and address of their

32

respective clients, as well as other information that will allow the Underwriters to properly identify their respective clients.

(d)           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.

(e)           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.

(f)            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.

(g)           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.

[signature page follows]

33

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

Signature Page to Underwriting Agreement

Confirmed and Accepted:  December 14, 2011

For themselves and on behalf of the several Underwriters listed in Schedule 1 hereto.

Signature Page to Underwriting Agreement

Schedule 1

Schedule 1 to Underwriting Agreement

Schedule 2

Lock-Up Parties

Laredo Petroleum Holdings, Inc.

Warburg Pincus Private Equity IX, L.P.

Warburg Pincus Private Equity X O&G, L.P.

Warburg Pincus X Partners, L.P.

WP IX Finance, LP

Randy A. Foutch

Jerry R. Schuyler

W. Mark Womble

Patrick J. Curth

John E. Minton

Rodney S. Myers

Peter R. Kagan

James R. Levy

B.Z. (Bill) Parker

Pamela S. Pierce

Francis Rooney

Edmund P. Segner, III

Donald D. Wolf

Schedule 2 to Underwriting Agreement

Schedule 3

Subsidiaries

Laredo Petroleum, Inc.  (Delaware)

Laredo Petroleum Texas, LLC (Texas)

Laredo Gas Services, LLC (Delaware)

Laredo Petroleum—Dallas, Inc.  (Delaware)

Schedule 3 to Underwriting Agreement

Annex A-1

[Form of Opinion of Counsel for Laredo Holdings]

1.                                       The Issuer is validly existing as a corporation and in good standing under the laws of the State of Delaware.

2.                                       Each of the Issuer and Laredo LLC has all requisite corporate or limited liability company, as applicable, power and authority to execute and deliver, and incur and perform all of its obligations under, the Transaction Documents.

3.                                       (a) The authorized capital stock of the Issuer consists of 450,000,000 shares of Common Stock and 50,000,000 shares of preferred stock, par value $0.01 per share. (b) Such capital stock conforms in all material respects as to legal matters to the description thereof set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the caption “Description of capital stock.”

4.                                       The Shares have been duly authorized and, when issued and delivered by the Issuer to the Underwriters against payment therefor in accordance with the Underwriting Agreement, will have been validly issued, will be fully paid and nonassessable and will not have been issued in violation of (a) any preemptive rights, resale rights, rights of first refusal or similar rights, (b) any outstanding options or warrants to purchase any equity securities of the Issuer, (c) any other agreement or obligation to issue any equity securities of the Issuer, or (d) any rights to convert any securities into or exchange or exercise any securities for any equity interest in the Issuer, in the case of clause (a), (b), (c) and (d), pursuant to or under the Governing Documents, any Material Agreement or any law, rule or regulation of any Included Law (as defined below).  Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus or previously waived or extinguished on or prior to the date hereof, there are no restrictions upon the voting or transfer of the Shares under the Governing Documents or under any Material Agreement.

5.                                       The holders of outstanding shares of capital stock of the Issuer are not entitled to any preemptive rights to subscribe for the Shares under the Governing Documents, the General Corporation Law of the State of Delaware or any of the Material Agreements.

6.                                       The execution and delivery of the Transaction Documents by each of the Issuer and Laredo LLC and the performance by each of the Issuer and Laredo LLC of its obligations thereunder have been duly authorized by all necessary corporate action by the Issuer and all necessary limited liability company action by Laredo LLC.

7.                                       The Underwriting Agreement has been duly and validly executed and delivered by each of the Issuer and Laredo LLC.

8.                                       (a) The Merger Agreement has been duly and validly executed and delivered by each of the Issuer and Laredo LLC.  (b) The Merger Agreement constitutes the valid and binding obligation of each of the Issuer and Laredo LLC, enforceable against each of the Issuer and Laredo LLC in accordance with its terms.  (c) The Merger has become effective at the Specified Effective Time under the Included Laws.

9.                                       The offering, issuance and sale of the Shares by the Issuer pursuant to the Underwriting Agreement and the execution and delivery of the Transaction Documents by each of the Issuer and Laredo LLC do not, and the performance by each of the Issuer and Laredo LLC of its obligations under the Transaction Documents will not, (a) result in any violation of any law, statute, rule or regulation of or under any Included Law (including Regulations T, U and X of the Board of Governors of the Federal Reserve System), (b) result in any violation of any order, writ, judgment or decree under any Included Law of any New York, Delaware or Federal governmental authority or regulatory body applicable to the Issuer or Laredo LLC or its respective assets or properties listed on Exhibit B hereto or (c) breach or result in a default, or result in the creation or imposition of any lien upon any property of the Issuer or Laredo LLC (other than any lien securing the Credit Agreement), under any Material Agreement.

10.                                 No Person has the right, which has not been waived, under any of the Governing Documents or Material Agreements to require the registration under the Securities Act of any sale of securities issued by the Issuer, by reason of the filing or effectiveness of the Registration Statement or any related prospectus forming part of the Registration Statement.

11.                                 No authorization or approval or other action by, and no notice to or filing with, any governmental authority or regulatory body (each, a “Filing”) is required under any of the Included Laws for the offering, issuance and sale of the Shares by the Issuer pursuant to the Underwriting Agreement, the due execution and delivery of the Transaction Documents by each of the Issuer and Laredo LLC and the performance by each of the Issuer and Laredo LLC of its obligations thereunder, except for (a) routine Filings necessary in connection with the conduct of the business of the Issuer, (b) such other Filings as have been obtained or made and (c) Filings under Federal and state securities Laws as required by the Transaction Documents.

12.                                 The statements in the Registration Statement, the Preliminary Prospectus and the Prospectus under the caption “Description of capital stock,” insofar as such statements purport to summarize certain provisions of documents referred to therein, fairly summarize such provisions in all material respects, subject to the qualifications and assumptions stated therein.  The statements in the Preliminary Prospectus and the Prospectus under the caption “Description of capital stock,” insofar as such statements purport to summarize provisions of any law, statute, rule or regulation of or under any Included Law referred to therein, fairly

summarize such laws, statutes, rules and regulations in all material respects, subject to the qualifications and assumptions stated therein.

13.                                 The statements in the Registration Statement, the Preliminary Prospectus and the Prospectus under the caption “Certain U.S. federal income tax considerations for non-U.S. holders of shares of our common stock,” insofar as such statements constitute a summary of the United States Federal tax laws referred to therein, as of the date of the Preliminary Prospectus and the Prospectus, in all material respects, are accurate and fairly summarize the United States federal tax laws referred to therein, subject to the qualifications and assumptions stated therein.

14.                                 The Issuer is not and, after giving effect to the Offering and sale of the Shares contemplated by the Underwriting Agreement and the application of the net proceeds from such sale as described in the Registration Statement, the Preliminary Prospectus and the Prospectus, will not be, required to register as an “investment company,” as such term is defined under the Investment Company Act of 1940, as amended.

15.                                 The Registration Statement was declared effective under the Securities Act on [  ], 2011.  To our knowledge, no stop order suspending the effectiveness of the Registration Statement has been issued and no proceedings for that purpose have been instituted or threatened by the Commission.  The filing of the Prospectus pursuant to Rule 424 under the Securities Act was made in the manner and within the time period required by such rule.

Our identification of [documents and other information described on Annex A hereto][the Free Writing Prospectus] as part of the Pricing Disclosure Package has been at your request and with your approval.  Such identification is for the limited purpose of making the statements set forth in this letter and is not the expression of a view by us as to whether any [such documents and information][the Free Writing Prospectus] has been or should have been conveyed to investors generally or to any particular investors at any particular time or in any particular manner.

Because the primary purpose of our professional engagement was not to establish or confirm factual matters, financial or accounting information or reserve or production information included in the Registration Statement, the Pricing Disclosure Package and the Prospectus, and because many determinations involved in the preparation of the Registration Statement, the Pricing Disclosure Package and the Prospectus are of a wholly or partially non-legal character, except as expressly set forth in paragraphs 3(b), 12 and 13 herein, we are not passing upon and do not assume any responsibility for the accuracy, completeness or fairness of the statements contained in the Registration Statement, the Prospectus or the Pricing Disclosure Package (the “Disclosure Documents”) and we make no representation that we have independently verified the accuracy, completeness or fairness of such statements.

However, in the course of our acting as special counsel to the Issuer in connection with the preparation of the Registration Statement, the Pricing Disclosure Package and the Prospectus, we have reviewed each Disclosure Document and have participated in conferences and telephone

conversations with representatives of the Issuer and Laredo LLC, representatives of the independent public accountants for the Issuer and Laredo LLC, representatives of the independent reserve engineers of the Issuer and Laredo LLC, representatives of the Underwriters and representatives of the Underwriters’ counsel, during which conferences and conversations the contents of such Disclosure Documents and related matters were discussed.

Based on our participation in such conferences and conversations, our review of the documents described above, our understanding of the United States Federal securities Laws and the experience we have gained in our practice thereunder, we advise you that:

(a)           Each of the Registration Statement, as of its effective date, the Preliminary Prospectus, as of its date, and the Prospectus, as of its date, appeared on its face to be appropriately responsive in all material respects to the requirements of the Securities Act, except that we express no view as to the financial statements, financial schedules and other financial and accounting data and reserve and production information contained therein;

(b)           There are no documents known to us that are required to be filed under the Securities Act as exhibits to the Registration Statement that are not so filed as required in all material respects, nor are there any documents known to us that are required under the Securities Act to be summarized in the Prospectus in the manner specified in the Securities Act that are not so summarized as required in all material respects, except that we express no view as to the financial statements, financial schedules and other financial and accounting data and reserve and production information so required to be filed or summarized; and

(c)           No information has come to our attention that causes us to believe that (i) the Registration Statement, at the time the Registration Statement became effective, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading; (ii) the Pricing Disclosure Package, as of [  ] (central time) on [  ], 2011 (which you have informed us is a time prior to the time of the first sale of the Shares by any Underwriter), contained any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they are made, not misleading or (iii) the Prospectus, as of the date of the Prospectus and as of the date hereof, contained or contains any untrue statement of a material fact or omitted or omits to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that in the case of each of clauses (i)-(iii) above, we do not express any view as to the financial statements, financial schedules and other financial and accounting data and reserve and production information contained therein.

Annex A-2

[Form of Opinion of General Counsel for Laredo Holdings]

1.                                       The Issuer has been duly incorporated as a corporation, and is validly existing and in good standing under the laws of the State of Delaware, the jurisdiction of its organization.  Laredo Inc. has been duly incorporated as a corporation, and is validly existing and in good standing under the laws of the State of Delaware, the jurisdiction of its organization.  Gas Services has been duly formed as a limited liability company, and is validly existing and in good standing under the laws of the State of Delaware, the jurisdiction of its organization.  Laredo Texas has been duly formed as a limited liability company, and is validly existing and in good standing under the laws of the State of Texas, the jurisdiction of its organization.  Laredo Dallas has been duly incorporated as a corporation, and is validly existing and in good standing under the laws of the State of Delaware, the jurisdiction of its organization.

2.                                       Laredo Inc. is duly qualified and is in good standing as a foreign corporation in the State of Oklahoma and the State of Texas.

3.                                       Gas Services is duly qualified and is in good standing as a foreign corporation in the State of Oklahoma and the State of Texas.

4.                                       Laredo Dallas is duly qualified and in good standing as a foreign corporation in the State of Texas.

5.                                       Each of the Subsidiaries has the corporate or limited liability company, as applicable, power and authority to own and hold its properties and conduct its business in all material respects as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

6.                                       The Issuer has the corporate power and authority to execute and deliver the Transaction Documents and to perform its obligations thereunder, and has the corporate power and authority to own and hold its properties and conduct its business in all material respects as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

7.                                       The offering, issuance and sale of the Shares by the Issuer pursuant to the Underwriting Agreement and the execution and delivery by each of the Issuer and Laredo LLC of the Transaction Documents do not, and the performance by each of the Issuer and Laredo LLC of its obligations thereunder will not, (a) result in a violation of the Governing Documents of the Issuer, Laredo LLC or any of the Subsidiaries, (b) result in any violation by the Issuer or Laredo LLC of any statute, rule or regulation under any Included Law applicable to Issuer or Laredo LLC, respectively, (c) breach or result in a default (or an event which, with notice or lapse of time, or both, would constitute a default), or result in the creation or imposition of any lien, charge, claim, encumbrance or other security interest (each, a “Lien”) upon any property or assets of the Issuer, Laredo LLC or any of

the Subsidiaries, under the Material Agreements, or (d) result in any violation of any order, writ, judgment or decree known to me after due inquiry.

8.                                       As of the date hereof, immediately prior to the issuance of the Shares, there were 107,500,000 shares of Common Stock issued and outstanding, all of which had been duly and validly authorized and issued and were fully paid and non-assessable and had not been issued in violation of (a) any preemptive rights, resale rights, rights of first refusal or similar rights, (b) any outstanding options or warrants to purchase any equity securities of the Issuer, (c) any other agreement or obligation to issue any equity securities of the Issuer, or (d) any rights to convert any securities into or exchange or exercise any securities for any equity interest in the Issuer, in the case of clause (a), (b), (c) and (d), pursuant to or under the Governing Documents of the Issuer, any Material Agreement or any law, rule or regulation of any Included Law.

9.                                       (a)  The Issuer owns of record 100% of the issued and outstanding shares of common stock of Laredo Inc., free and clear of all Liens in respect of which a financing statement under the Uniform Commercial Code of the State of Delaware (the “UCC”) naming the Issuer as the debtor is on file in the office of the Secretary of State of the State of Delaware, other than those Liens that are (i) created under the General Corporation Law of the State of Delaware, (ii) created pursuant to Laredo Inc.’s Third Amended and Restated Credit Agreement, as amended to the date hereof, and described on Exhibit C hereto (as so amended, the “Credit Agreement”), (iii) created by the Governing Documents of Laredo Inc., or (iv) disclosed in the Preliminary Prospectus and the Prospectus.  Such shares of common stock have been duly authorized and validly issued and are fully paid and non-assessable.

(b)  Laredo Inc. owns of record 100% of the issued and outstanding membership interests in Gas Services, free and clear of all Liens in respect of which a financing statement under the UCC naming Laredo Inc. as the debtor is on file in the office of the Secretary of State of the State of Delaware, other than those Liens that are (i) created under the Limited Liability Company Act of the State of Delaware, (ii) created pursuant to the Credit Agreement, (iii) created by the Governing Documents of Gas Services, or (iv) disclosed in the Preliminary Prospectus and the Prospectus.  Such membership interests have been duly authorized and validly issued in accordance with the Governing Documents of Gas Services and are fully paid (to the extent required under the Governing Documents of Gas Services) and non-assessable (except as such non-assessability may be affected by Sections 18-607 and 18-804 of the Limited Liability Company Act of the State of Delaware).

(c)  Laredo Inc. owns of record 100% of the issued and outstanding membership interests in Laredo Texas, free and clear of all Liens in respect of which a financing statement under the UCC naming Laredo Inc. as the debtor is on file in the office of the Secretary of State of the State of Delaware, other than those Liens that are (i) created under Texas Business Organization Code, (ii) created

pursuant to the Credit Agreement, (iii) created by the Governing Documents of Laredo Texas, or (iv) disclosed in the Preliminary Prospectus and the Prospectus.  Such membership interests have been duly authorized and validly issued in accordance with the Governing Documents of Laredo Texas and are fully paid (to the extent required under the Governing Documents of Laredo Texas) and non-assessable (except as such non-assessability may be affected by Sections 101.206 and 101.613 of the Texas Business Organization Code).

(d)  Laredo Inc. owns of record 100% of the issued and outstanding shares of common stock in Laredo Dallas, free and clear of all Liens in respect of which a financing statement under the UCC naming Laredo Inc. as the debtor is on file in the office of the Secretary of State of the State of Delaware, other than those Liens that are (i) created under the General Corporation Law of the State of Delaware, (ii) created pursuant to the Credit Agreement, (iii) created by the Governing Documents of Laredo Dallas, or (iv) disclosed in the Preliminary Prospectus and the Prospectus.  Such shares of common stock have been duly authorized and validly issued and are fully paid and non-assessable.

10.                                 (a)  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are, to my knowledge after due inquiry, no actions, suits or proceedings pending or threatened in writing against the Issuer, before any court or arbitrator(s) or by or before any administrative agency or government authority, in which there is a reasonable possibility of an adverse decision that could reasonably be expected to (i) have a Material Adverse Effect, (ii) call into question the validity or enforceability of the Transaction Documents, or (iii) materially and adversely affect the ability of the Issuer to perform its obligations under the Transaction Documents.

(b)  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are, to my knowledge after due inquiry, no actions, suits or proceedings pending or threatened in writing against Laredo Inc., before any court or arbitrator(s) or by or before any administrative agency or government authority, in which there is a reasonable possibility of an adverse decision that could reasonably be expected to have a Material Adverse Effect.

(c)  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are, to my knowledge after due inquiry, no actions, suits or proceedings pending or threatened in writing against Gas Services, before any court or arbitrator(s) or by or before any administrative agency or government authority, in which there is a reasonable possibility of an adverse decision that could reasonably be expected to have a Material Adverse Effect.

(d)  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are, to my knowledge after due inquiry, no actions, suits or proceedings pending or threatened in writing against Laredo Texas, before any court or arbitrator(s) or by or before any administrative agency

or government authority, in which there is a reasonable possibility of an adverse decision that could reasonably be expected to have a Material Adverse Effect.

(e)  Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are, to my knowledge after due inquiry, no actions, suits or proceedings pending or threatened in writing against Laredo Dallas, before any court or arbitrator(s) or by or before any administrative agency or government authority, in which there is a reasonable possibility of an adverse decision that could reasonably be expected to have a Material Adverse Effect.

11.                                 No authorization or approval or other action by, and no notice to or filing with, any governmental authority or regulatory body (each, a “Filing”) is required under any of the Included Laws for the offering, issuance and sale of the Shares by the Issuer pursuant to the Underwriting Agreement, the due execution and delivery of the Transaction Documents by each of the Issuer and Laredo LLC and the performance by each of the Issuer and Laredo LLC of its obligations thereunder, except for (a) routine Filings necessary in connection with the conduct of the business of the Issuer, (b) such other Filings as have been obtained or made, and (c) Filings under Federal and state securities Laws as required by the Transaction Documents.

Annex B

a.             Pricing Disclosure Package

None.

b.             Pricing Information Provided Orally by Underwriters

Price per share to the public: $17.00

Number of Shares Offered: 17,500,000

Annex B to Underwriting Agreement

Exhibit A

FORM OF LOCK-UP AGREEMENT

December 14, 2011

J.P. Morgan Securities LLC
Goldman, Sachs & Co.

Merrill Lynch, Pierce, Fenner & Smith

Incorporated

Wells Fargo Securities, LLC

As Representatives of
the several Underwriters listed in
Schedule 1 to the Underwriting
Agreement referred to below

c/o J.P. Morgan Securities LLC
383 Madison Avenue
New York, NY 10179

Re:          Laredo Petroleum Holdings, Inc.

Ladies and Gentlemen:

The undersigned understands that you, as Representatives of the several Underwriters, propose to enter into an Underwriting Agreement (the “Underwriting Agreement”) with Laredo Petroleum Holdings, Inc., a Delaware corporation (the “Company”), providing for the public offering (the “Public Offering”) by the several Underwriters named in Schedule 1 to the Underwriting Agreement (the “Underwriters”), of common stock, $0.01 per share par value (the “Common Stock”), of the Company (the “Securities”). Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Underwriting Agreement.

In consideration of the Underwriters’ agreement to purchase and make the Public Offering of the Securities, and for other good and valuable consideration receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of J.P. Morgan Securities LLC, Goldman, Sachs & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, the undersigned will not, during the period ending 180 days after the date of the prospectus relating to the Public Offering (the “Prospectus”), (1) 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 Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (including without limitation, Common Stock or such other securities which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of

Exhibit A-1

a stock option or warrant), or publicly disclose the intention to make any offer, sale, pledge, disposition or filing (other than any filings on Form S-8 relating to the Company Stock Plans), (2) 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 or such other securities, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, or (3) make any demand for or exercise any right with respect to the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock; provided, however, (x) Warburg Pincus, LLC will be permitted to spin-off our Common Stock that it owns to its shareholders 180 days after the date of the Prospectus and (y) the foregoing provisions will not restrict transfers of Common Stock as bona fide gifts, transfers by will or the laws of intestacy, transfers to family members (including to vehicles of which they are beneficial owners), transfers pursuant to domestic relations or court orders, or (in the case of corporations or other entities) transfers to affiliates, in each case, so long as the transferee agrees to be bound by the restrictions set forth herein and such transfer is not required to be reported with the Securities and Exchange Commission on Form 4 in accordance with Section 16 of the Securities Exchange Act of 1934, as amended.

If the undersigned is an officer or director of the Company, (i) J.P. Morgan Securities LLC, Goldman, Sachs & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, on behalf of the Underwriters, agree that, at least three business days before the effective date of any release or waiver of the foregoing restrictions in connection with a transfer of shares of Common Stock, J.P. Morgan Securities LLC, Goldman, Sachs & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, on behalf of the Underwriters, will notify the Company of the impending release or waiver, and (ii) the Company has agreed in the Underwriting Agreement to announce the impending release or waiver by press release through a major news service at least two business days before the effective date of the release or waiver.  Any release or waiver granted by J.P. Morgan Securities LLC, Goldman, Sachs & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, on behalf of the Underwriters, hereunder to any such officer or director shall only be effective two business days after the publication date of such press release.  The provisions of this paragraph will not apply if (a) the release or waiver is effected solely to permit a transfer not for consideration and (b) the transferee has agreed in writing to be bound by the same terms described in this letter to the extent and for the duration that such terms remain in effect at the time of the transfer.

Notwithstanding the foregoing, if (1) during the last 17 days of the 180-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 180-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 180-day period, the restrictions imposed by this Letter Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release, announcement of the material news or occurrence of the material event.

In furtherance of the foregoing, the Company, and any duly appointed transfer agent for the registration or transfer of the securities described herein, are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Letter Agreement.

Exhibit A-2

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Letter Agreement.  All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

The undersigned understands that, if the Underwriting Agreement does not become effective, or if the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Common Stock to be sold thereunder, the undersigned shall be released from, all obligations under this Letter Agreement.  The undersigned understands that the Underwriters are entering into the Underwriting Agreement and proceeding with the Public Offering in reliance upon this Letter Agreement.

This Letter Agreement and any claim, controversy or dispute arising under or related to this Letter Agreement shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflict of laws principles thereof.

Exhibit A-3

Exhibit B

[Form of Press Release]

Laredo Petroleum Holdings, Inc.
[Date]

Laredo Petroleum Holdings, Inc. (the “Company”) announced today that J.P. Morgan Securities LLC, the lead book-running manager in the Company’s recent public sale of            shares of common stock, is [waiving] [releasing] a lock-up restriction with respect to              shares of the Company’s common stock held by [certain officers or directors] [an officer or director] of the Company. The [waiver] [release] will take effect on                                      , 20    , and the shares may be sold on or after such date.

This press release is not an offer for sale of the securities in the United States or in any other jurisdiction where such offer is prohibited, and such securities may not be offered or sold in the United States absent registration or an exemption from registration under the United States Securities Act of 1933, as amended.

Exhibit B to Underwriting Agreement