UNDERWRITING AGREEMENT

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Exhibit 1.1

11,750,000 Common Units

LINN ENERGY, LLC

Representing Limited Liability Company Interests

UNDERWRITING AGREEMENT

January [    •    ], 2006

RBC Capital Markets Corporation
Lehman Brothers Inc.
A.G. Edwards & Sons, Inc.
UBS Securities LLC
KeyBanc Capital Markets, a Division of McDonald Investments Inc.
Raymond James & Associates, Inc.

c/o RBC Capital Markets Corporation
60 South Sixth Street
Minneapolis, MN 55402

c/o Lehman Brothers Inc.
745 Seventh Avenue
New York, NY 10019

Ladies and Gentlemen:

        Linn Energy, LLC, a Delaware limited liability company (the " Company "), proposes to issue and sell to the several underwriters named in Schedule I hereto (the " Underwriters ") an aggregate of 11,750,000 units (the " Firm Units ") representing limited liability company interests of the Company (" Units "). The respective amounts of the Firm Units to be so purchased by the several Underwriters are set forth opposite their names in Schedule I hereto. The Company also proposes to sell at the Underwriters' option an aggregate of up to 1,762,500 additional Units (the " Option Units ") as set forth below. The Firm Units and the Option Units (to the extent the aforementioned option is exercised) are collectively referred to herein as the " Offered Units ." This is to confirm the agreement among (i) the Company, (ii) Linn Operating, Inc., a Delaware corporation (" Linn Operating "), (iii) Linn Energy Holdings, LLC, a Delaware limited liability company (" Linn Holdings "), (iv) Chipperco, LLC, a Delaware limited liability company (" Chipperco "), (v) Mid Atlantic Well Services, Inc., a Delaware corporation (" Mid Atlantic "), (vi) Quantum Energy Partners II, LP, a Delaware limited partnership (" Quantum ") and (vii) the Underwriters concerning the purchase of the Offered Units from the Company by the Underwriters. The Company, Linn Operating, Linn Holdings, Chipperco and Mid Atlantic are referred to herein collectively as the " Linn Energy Entities ."

        In consideration of the mutual agreements contained herein and of the interests of the parties in the transactions contemplated hereby, the parties hereto agree as follows:

        1.     REPRESENTATIONS AND WARRANTIES OF THE LINN ENERGY ENTITIES.     Each of the Linn Energy Entities represents and warrants to each of the Underwriters as follows:

        (a)     Registration Statement and Prospectus.     A registration statement on Form S-1 (File No. 333-125501) with respect to the Units has (i) been prepared by the Company in conformity with the requirements of the Securities Act of 1933, as amended (the " Securities Act "), and the rules and regulations (the " Rules and Regulations ") of the United States Securities and Exchange Commission (the " Commission ") thereunder, (ii) been filed with the Commission under the Securities Act and (iii) become effective under the Securities Act. Copies of such registration statement and each of the amendments thereto have been delivered by the Company to you. As

used in this Agreement, " Effective Time " means the date and the time as of which such registration statement, or the most recent post-effective amendment thereto, if any, was declared effective by the Commission; " Effective Date " means the date of the Effective Time; " Preliminary Prospectus " means each prospectus included in such registration statement, or amendments thereof, before it became effective under the Securities Act and any prospectus filed with the Commission by the Company with the consent of the Underwriters pursuant to Rule 424(a) of the Rules and Regulations; " Prospectus " means the prospectus in the form first filed pursuant to Rule 424(b) under the Securities Act; the Preliminary Prospectus relating to the Offered Units that was included in the Registration Statement immediately prior to the Applicable Time (as defined in Section 1(c) hereof) is hereinafter called the " Pricing Prospectus "; " Registration Statement " means such registration statement, as amended at the Effective Time, including all information contained in the final prospectus filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations and deemed to be a part of the registration statement as of the Effective Time pursuant to Rule 430A of the Rules and Regulations; and any "issuer free writing prospectus" as defined in Rule 433 under the Securities Act relating to the Offered Units is hereinafter called an " Issuer Free Writing Prospectus ." If the Company has filed an abbreviated registration statement to register additional Common Units 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. For the purposes of this Agreement, the " Applicable Time " is    :       m (Eastern time) on the date of this Agreement.

        The Pricing Prospectus, as supplemented by the Issuer Free Writing Prospectuses and other documents listed in Schedule II(a) hereto, taken together (collectively, the " Pricing Disclosure Package ") as of the Applicable Time, did not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; and each Issuer Free Writing Prospectus listed on Schedule II(a) or Schedule II(b) hereto does not conflict with the information contained in the Registration Statement, the Pricing Prospectus or the Prospectus, and each such Issuer Free Writing Prospectus, as supplemented by and taken together with the Pricing Disclosure Package as of the Applicable Time, did not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that this representation and warranty shall not apply to statements or omissions made in an Issuer Free Writing Prospectus in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through RBC Capital Markets Corporation or Lehman Brothers Inc. expressly for use therein. The Commission has not issued any order preventing or suspending the use of any Preliminary Prospectus or any Issuer Free Writing Prospectus.

        (b)     No Material Misstatements or Omissions.     The Registration Statement conforms, and any further amendments or supplements to the Registration Statement will, when they become effective, conform in all material respects to the requirements of the Securities Act and the Rules and Regulations and do not and will not, as of the applicable effective date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. The Prospectus conforms, and any further amendments or supplements to the Prospectus will, when they are filed with the Commission, conform in all material respects to the requirements of the Securities Act and the Rules and Regulations and do not and will not, as of the applicable filing date, contain an untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. Each of the statements made by the Company in such documents within the coverage of Rule 175(b) of the Rules and Regulations, including (but not limited to) any projections, results of operations or statements with respect to future available cash or future cash distributions of the Company or the

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anticipated ratio of taxable income to distributions, was made or will be made with a reasonable basis and in good faith. Notwithstanding the foregoing, this representation and warranty shall not apply to any statements or omissions made in reliance upon and in conformity with written information concerning the Underwriters furnished to the Company by or on behalf of any Underwriter specifically for inclusion in the Registration Statement, the Pricing Prospectus or the Prospectus.

        (c)     Formation and Qualification of the Company, Linn Holdings and Chipperco.     Each of the Company, Linn Holdings and Chipperco (collectively, the " Delaware LLCs ") has been duly formed and is validly existing as a limited liability company in good standing under the Delaware Limited Liability Company Act (the " Delaware LLC Act "), and is, or at each Closing Date (as defined in Section 3 of this Agreement) will be, duly registered or qualified to do business and is in good standing as a foreign limited liability company in each jurisdiction in which its ownership or lease of property or the conduct of its businesses requires such registration or qualification, except where the failure so to register or qualify would not (i) have a material adverse effect on the consolidated financial position, members' capital, results of operations, business or prospects of the Linn Energy Entities taken as a whole (a " Material Adverse Effect ") or (ii) subject the members of the Company to any material liability or disability. Each of the Delaware LLCs has all limited liability company power and authority necessary to own or lease its properties currently owned or leased or to be owned or leased at each Closing Date, and to conduct its business as currently conducted or to be conducted at each Closing Date, in each case in all material respects as described in the Registration Statement and the Pricing Prospectus.

        (d)     Formation and Qualification of Linn Operating and Mid Atlantic.     Each of Linn Operating and Mid Atlantic has been duly formed and is validly existing as a corporation in good standing under the Delaware General Corporation Law (the " DGCL "), and is, or at each Closing Date will be, duly registered or qualified to do business and is in good standing as a foreign corporation in each jurisdiction in which its ownership or lease of property or the conduct of its businesses requires such registration or qualification, except where the failure so to register or qualify would not (i) have a Material Adverse Effect or (ii) subject the members of the Company to any material liability or disability. Each of Linn Operating and Mid Atlantic has all corporate power and authority necessary to own or lease its properties and to conduct its business as currently conducted or to be conducted at each Closing Date, in each case in all material respects as described in the Registration Statement and the Pricing Prospectus.

        (e)     Ownership of the Existing Investor Units.     Assuming no purchase by the Underwriters of Option Units on the First Closing Date (as defined in Section 2 of this Agreement), at the First Closing Date, after giving effect to the transactions contemplated by that certain Stakeholders' Agreement dated June 2, 2005 (the " Stakeholders' Agreement "), (i) the Company's management (excluding Units owned by Quantum that may be deemed to be beneficially owned by Toby R. Neugebauer) will beneficially own [4,867,235] Units, (ii) Quantum will beneficially own [10,914,228] Units and (iii) Clark Partners I, L.P., Kings Highway Investments, LLC and Wauwinet Energy Partners, LLC will beneficially own [281,037] Units in the aggregate (collectively, the " Existing Investor Units "). The Company's management and Quantum are referred to collectively as the " Existing Investors ." At each Closing Date, all of such Existing Investor Units and the limited liability company interests represented thereby will be duly authorized and validly issued in accordance with the Second Amended and Restated Limited Liability Company Agreement of the Company (the " Limited Liability Company Agreement ") and will be fully paid (to the extent required under the Limited Liability Company Agreement) and nonassessable (except as such nonassessability may be affected by matters described in the Pricing Prospectus under the caption "The Limited Liability Company Agreement—Limited Liability").

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        (f)     Valid Issuance of the Units.     At the First Closing Date, there will be issued to the Underwriters the Firm Units (assuming no purchase by the Underwriters of Option Units on the First Closing Date); at the First Closing Date or the Second Closing Date (as defined in Section 2 of this Agreement), as the case may be, the Firm Units and the Option Units, as the case may be, and the limited liability company interests represented thereby, will be duly authorized in accordance with the Limited Liability Company Agreement and, when issued and delivered against payment therefor in accordance with this Agreement, will be validly issued, fully paid (to the extent required under the Limited Liability Company Agreement) and nonassessable (except as such nonassessability may be affected by matters described in the Pricing Prospectus under the caption "The Limited Liability Company Agreement—Limited Liability"). Other than the Existing Investor Units, the Offered Units will be the only limited liability company interests of the Company issued and outstanding at each Closing Date.

        (g)     Ownership of Linn Holding and Chipperco.     At each Closing Date, the Company will own 100% of the limited liability company interests of each of Linn Holdings and Chipperco. At each Closing Date, such limited liability company interests will be duly authorized and validly issued in accordance with the certificate of formation and limited liability company agreement of each such limited liability company and will be fully paid (to the extent required under the applicable limited liability company's certificate of formation and limited liability company agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Company will own all such interests free and clear of all liens, encumbrances, security interests, charges and other adverse claims, except for liens created under the Credit Agreement (as defined in Section 17).

        (h)     Ownership of Linn Operating and Mid Atlantic.     At each Closing Date, the Company will own 100% of the outstanding capital stock of Linn Operating and Mid Atlantic. At each Closing Date, such capital stock will be duly authorized and validly issued in accordance with the certificate of incorporation and bylaws of Linn Operating and Mid Atlantic and will be fully paid and nonassessable; and the Company will own all such capital stock free and clear of all liens, encumbrances, security interests, charges and other adverse claims, except for liens created under the Credit Agreement.

        (i)     No Other Subsidiaries.     Other than its ownership interests in Linn Holding, Linn Operating, Chipperco and Mid Atlantic, the Company does not own and at each Closing Date will not own, directly or indirectly, any equity or long-term debt securities of any corporation, partnership, limited liability company, joint venture, association or other entity.

        (j)     No Preemptive Rights, Registration Rights or Options.     Except as described in the Pricing Prospectus, there are no preemptive rights or other rights to subscribe for or to purchase, nor any restriction upon the voting or transfer of any equity securities in any of the Linn Energy Entities. Neither the filing of the Registration Statement nor the offering or sale of the Offered Units as contemplated by this Agreement gives rise to any rights for or relating to the registration of any Units or other securities of any of the Linn Energy Entities other than as provided in the Pricing Prospectus and the Limited Liability Company Agreement or as have been waived. Except as described in the Pricing Prospectus, there are no outstanding options or warrants to purchase (A) any Units or other interests in the Company or (B) any membership interest or capital stock of any of the other Linn Energy Entities.

        (k)     Capitalization.     As of September 30, 2005, the Company would have had, on the consolidated pro forma basis indicated in the Pricing Prospectus (and any amendment or supplement thereto), a capitalization as set forth therein.

        (l)     Authority and Authorization.     The Company has all requisite limited liability company power and authority to issue, sell and deliver (i) the Offered Units, in accordance with and upon

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the terms and conditions set forth in this Agreement and the Limited Liability Company Agreement, and (ii) the Existing Investor Units, in accordance with and upon the terms and conditions set forth in the Limited Liability Company Agreement. At the First Closing Date and the Second Closing Date (as defined in Section 3 of this Agreement), all corporate, partnership and limited liability company action, as the case may be, required to be taken by the Linn Energy Entities or any of their stockholders or members for the authorization, issuance, sale and delivery of the Offered Units and the Existing Investor Units, the execution and delivery by the Linn Energy Entities of this Agreement and the consummation of the transactions contemplated by this Agreement shall have been validly taken.

        (m)     Enforceability of Agreement.     This Agreement has been duly authorized and validly executed and delivered by each of the Linn Energy Entities and constitutes the valid and legally binding agreement of each of the Linn Energy Entities, enforceable against each of them in accordance with its terms; provided that the enforceability hereof 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); provided, further , that the indemnity, contribution and exoneration provisions contained hereunder may be limited by applicable laws and public policy.

        (n)     Enforceability of Other Agreements.     At or before the First Closing Date:

(1)

the Limited Liability Company Agreement will have been duly authorized, executed and delivered by the Members (as defined in the Limited Liability Company Agreement) and will be a valid and legally binding agreement of the Initial Members (as defined in the Limited Liability Company Agreement) and the Members, enforceable against the Initial Members and the Members in accordance with its terms;

(2)

the certificate of formation, limited liability company agreement, certificate of incorporation, bylaws or other organizational documents, as applicable, (the " Linn Energy Entities Operative Documents ") will have been duly authorized, executed and delivered by the Linn Energy Entities that are parties thereto, as applicable, and will be a valid and legally binding agreement of the respective parties thereto, enforceable against the Linn Energy Entities that are parties thereto in accordance with its terms; and

(3)

the Credit Agreement (as defined in Section 17 hereof) has been duly authorized, executed and delivered by the Linn Energy Entities that are parties thereto and will be a valid and legally binding agreement of the respective parties, enforceable against the Linn Energy Entities that are parties thereto in accordance with its terms;

provided that, with respect to each agreement described in this Section 1(o), the enforceability thereof may be limited by (i) 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) and (ii) public policy, applicable law relating to fiduciary duties and indemnification and an implied covenant of good faith and fair dealing; provided, further , that the indemnity, contribution and exoneration provisions contained in any of such agreements may be limited by applicable laws and public policy.

        (o)     No Conflicts.     None of the offering, issuance and sale by the Company of the Offered Units, the execution, delivery and performance of this Agreement and the Credit Agreement by the Linn Energy Entities that are parties hereto and thereto or the consummation of the

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transactions contemplated hereby or thereby (i) conflicts or will conflict with or constitutes or will constitute a violation of any of the Linn Energy Operative Documents, (ii) conflicts or will conflict with or constitutes or will constitute a breach or violation of, or a default under (or an event which, with notice or lapse of time or both, would constitute such a default), any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which any of the Linn Energy Entities is a party or by which any of them or any of their respective properties may be bound, (iii) violates or will violate any statute, law or regulation or any order, judgment, decree or injunction of any court or governmental agency or body having jurisdiction over any of the Linn Energy Entities or any of their properties in a proceeding to which any of them or their property is or was a party, or (iv) results or will result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of any of the Linn Energy Entities, which conflicts, breaches, violations, defaults or liens, in the case of clauses (ii), (iii) or (iv), would have, individually or in the aggregate, a Material Adverse Effect.

        (p)     No Consents.     Except for (i) the registration of the Offered Units under the Securities Act, (ii) such consents, approvals, authorizations, registrations or qualifications as may be required under the Securities Exchange Act of 1934, as amended (the " Exchange Act "), and applicable state securities laws in connection with the purchase and distribution of the Units by the Underwriters, (iii) such consents that have been, or prior to each Closing Date will be, obtained, (iv) such consents that, if not obtained, would not, individually or in the aggregate, have a Material Adverse Effect, and (v) as disclosed in the Prospectus, no consent, approval, authorization or order of, or filing or registration with, any court or governmental agency or body having jurisdiction over the Linn Energy Entities or any of their respective properties is required in connection with the offering, issuance and sale by the Company of the Offered Units, the execution, delivery and performance of this Agreement and the Linn Energy Operative Documents by the Linn Energy Entities and the consummation of the transactions contemplated hereby and thereby.

        (q)     No Default .    None of the Linn Energy Entities (i) is in violation of its applicable Linn Energy Operative Documents, (ii) is in default, and no event has occurred which, 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 it is a party or by which it is bound or to which any of its properties or assets is subject or (iii) is in violation of any law, statute, ordinance, administrative or governmental rule or regulation applicable to it or of any order, judgment, decree or injunction of any court or governmental agency or body having jurisdiction over it, which default or violation in the case of clause (ii) or (iii), would, if continued, have a Material Adverse Effect, or could materially impair the ability of any of the Linn Energy Entities to perform their obligations under this Agreement. To the knowledge of each of the Linn Energy Entities, no third party to any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which any of the Linn Energy Entities is a party or by which any of them is bound or to which any of their respective properties is subject, is in default under any such agreement, which default would, if continued, have a Material Adverse Effect.

        (r)     Conformity to Description of Units and Existing Investor Units .    The Offered Units, when issued and delivered in accordance with the terms of the Limited Liability Company Agreement against payment therefor as provided herein, will conform, and the Existing Investor Units do conform, in all material respects to the descriptions thereof contained in the Pricing Prospectus.

        (s)     No Material Adverse Changes .    None of the Linn Energy Entities has sustained, since the date of the latest audited financial statements included in the Pricing Prospectus, any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order, investigation or decree, otherwise than as set forth or contemplated in the Pricing Prospectus; and,

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since such date, there has not been any material change in the capitalization or long-term debt of any of the Linn Energy Entities or any material adverse change, or any development involving, or which may reasonably be expected to involve, singly or in the aggregate, a prospective material adverse change in or affecting the general affairs, management, consolidated financial position, stockholders' equity, members' capital, results of operations, business or prospects of the Linn Energy Entities, taken as a whole, otherwise than as set forth or contemplated in the Pricing Prospectus. Since the date of the latest audited financial statements included in the Pricing Prospectus, none of the Linn Energy Entities has incurred any liability or obligation, direct, indirect or contingent, or entered into any transactions, not in the ordinary course of business, that, singly or in the aggregate, is material to the Linn Energy Entities, taken as a whole otherwise than as set forth or contemplated in the Pricing Prospectus.

        (t)     Financial Statements .    The historical consolidated financial statements (including the related notes and supporting schedules) filed as part of the Registration Statement or included in the Pricing Prospectus (and any amendment or supplement thereto) present fairly in all material respects the financial condition and results of operations of the entities purported to be shown thereby on the basis stated therein, at the dates and for the periods indicated, and have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods involved. The summary historical and pro forma consolidated financial and operating information set forth in the Registration Statement and the Pricing Prospectus (and any amendment or supplement thereto) under the caption "Summary Historical and Pro Forma Consolidated Financial and Operating Data" and the selected historical and pro forma consolidated financial and operating information set forth under the caption "Selected Historical and Pro Forma Consolidated Financial Data" set forth in the Registration Statement and the Pricing Prospectus is presented fairly in all material respects and prepared on a basis consistent with the audited and unaudited historical consolidated financial statements and pro forma financial statements, as applicable, from which it has been derived. The unaudited pro forma financial statements of the Company included in the Registration Statement and the Pricing Prospectus (and any amendment or supplement thereto) have been prepared in all material respects in accordance with the applicable requirements of Article 11 of Regulation S-X of the Securities Act; the assumptions used in the preparation of such unaudited pro forma financial statements are, in the opinion of the management of the Company, reasonable; and the pro forma adjustments reflected in such unaudited pro forma financial statements have been properly applied to the historical amounts in compilation of such unaudited pro forma financial statements.

        (u)     Independent Public Accountants .    KPMG LLP, who has certified certain financial statements of the Company, and whose report appears in the Pricing Prospectus and who has delivered the letters referred to in Section 7(e) hereof, were independent public accountants as with respect to the Company required by the Securities Act and the Rules and Regulations during the periods covered by the financial statements on which they reported.

        (v)     Independent Public Accountants .    Toothman Rice, PLLC, who has certified certain financial statements relating to certain acquisitions, and whose report appears in the Pricing Prospectus and who has delivered the letters referred to in Section 7(e) hereof, were independent public accountants with respect to the Company as required by the Securities Act and the Rules and Regulations during the periods covered by the financial statements on which they reported.

        (w)     Independent Public Accountants .    Elms, Faris & Co., LP, who has certified certain financial statements relating to certain acquisitions, and whose report appears in the Pricing Prospectus, were independent public accountants with respect to the Company as required by the Securities Act and the Rules and Regulations during the periods covered by the financial statements on which they reported.

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        (x)     Independent Public Accountants .    Hantzman Wiebel LLP, who has certified certain financial statements relating to certain acquisitions, and whose report appears in the Pricing Prospectus, were independent public accountants with respect to the Company as required by the Securities Act and the Rules and Regulations during the periods covered by the financial statements on which they reported.

        (y)     Independent Petroleum Engineers .    Schlumberger Data & Consulting Services, whose report dated November 7, 2005 is referenced in the Pricing Prospectus and who has delivered the letter referred to in Section 7(g) hereof, was, as of the date of such report, and is, as of the date hereof, an independent petroleum engineer with respect to the Company.

        (z)     Title to Real Property .    At each Closing Date, each of the Linn Energy Entities will have good, valid and indefeasible title to all of the interests in oil and gas properties underlying the Linn Energy Entities estimates of its net proved reserves contained in the Pricing Prospectus and to all other real and personal property reflected in the Pricing Prospectus as assets owned by them, in each case, free and clear of all (i) liens and security interests or (ii) other claims and other encumbrances (other than liens or security interests) except, in each case, (1) as described, and subject to the limitations contained, in the Pricing Prospectus or (2) such as do not materially interfere with the use of such properties taken as a whole as they have been used in the past and are proposed to be used in the future as described in the Pricing Prospectus; provided that, with respect to any real property and buildings held under lease by any Linn Energy Entity, such real property and buildings are held under valid and subsisting and enforceable leases with such exceptions as do not materially interfere with the use of the properties of the Linn Energy Entities taken as a whole as they have been used in the past as described in the Pricing Prospectus and are proposed to be used in the future as described in the Pricing Prospectus; the working interests derived from oil, gas and mineral leases or mineral interests which constitute a portion of the real property held or leased by the Linn Energy Entities reflect in all material respects the right of the Linn Energy Entities to explore, develop or produce hydrocarbons from such real property, and the care taken by the Linn Energy Entities with respect to acquiring or otherwise procuring such leases or mineral interests was generally consistent with standard industry practices in the areas in which the Linn Energy Entities operate for acquiring or procuring leases and interests therein to explore, develop or produce hydrocarbons.

        (aa)     Information Underlying Reserve Report .    The information underlying the estimates of reserves of the Linn Energy Entities, which was supplied by the Linn Energy Entities to Schlumberger Data & Consulting Services for purposes of reviewing the reserve reports and estimates of the Linn Energy Entities and preparing the respective letters (the " Reserve Report Letter ") of Schlumberger Data & Consulting Services included as annexes to the Prospectus, including, without limitation, production, costs of operation and development, current prices for production, agreements relating to current and future operations and sales of production, was true and correct in all material respects on the dates such estimates were made and such information was supplied and was prepared in accordance with customary industry practices; other than normal production of the reserves and intervening market commodity price fluctuations described in the Pricing Prospectus, the Linn Energy Entities are not aware of any facts or circumstances that would result in a material adverse change in the reserves, or the present value of future net cash flows therefrom, as described in the Pricing Prospectus and as reflected in the Reserve Report Letter; estimates of such reserves and present values as described in the Pricing Prospectus and reflected in the Reserve Report Letter comply in all material respects with the applicable requirements of Regulation S-X and Industry Guide 2 under the Securities Act.

        (bb)     Insurance .    The Linn Energy Entities maintain insurance covering their properties, operations, personnel and businesses against such losses and risks and in such amounts as is reasonably adequate for the conduct of their respective businesses and the value of their respective

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properties and as is customary for companies engaged in similar businesses in similar industries. None of the Linn Energy Entities has received notice from any insurer or agent of such insurer that substantial capital improvements or other expenditures will have to be made in order to continue such insurance, and all such insurance is outstanding and duly in force on the date hereof and will be outstanding and duly in force on each Closing Date.

        (cc)     Legal Proceedings or Contracts to be Described or Filed .    There are no legal or governmental proceedings pending or, to the knowledge of the Linn Energy Entities, threatened against any of the Linn Energy Entities, or to which any of the Linn Energy Entities is a party, or to which any of their respective properties is subject, that are required to be described in the Registration Statement or the Pricing Prospectus and are not described as required; and there are no agreements, contracts, indentures, leases or other instruments that are required to be described in the Registration Statement or the Pricing Prospectus or to be filed as exhibits to the Registration Statement by the Securities Act or by the Rules and Regulations that have not been described in the Registration Statement or the Pricing Prospectus as required or filed as exhibits to the Registration Statement as required.

        (dd)     Certain Relationships and Related Transactions .    No relationship, direct or indirect, exists between or among any Linn Energy Entity, on the one hand, and the directors, officers, members, partners, stockholders, customers or suppliers of any Linn Energy Entity on the other hand that is required to be described in the Pricing Prospectus that is not so described. There are no outstanding loans, advances (except normal advances for business expenses in the ordinary course of business) or guarantees of indebtedness by any Linn Energy Entity to or for the benefit of any of the officers or directors of any Linn Energy Entity or their respective family members, except as disclosed in the Registration Statement and the Pricing Prospectus. No Linn Energy Entity has, in violation of the Sarbanes-Oxley Act of 2002, directly or indirectly, extended or maintained credit, arranged for the extension of credit, or renewed an extension of credit, in the form of a personal loan to or for any director or executive officer of any Linn Energy Entity.

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

        (ff)     No Labor Dispute .    No labor dispute with the employees of any Linn Energy Entity exists or, to the knowledge of the Linn Energy Entities, is imminent or threatened that is reasonably likely to result in a Material Adverse Effect.

        (gg)     Tax Returns .    Each of the Linn Energy Entities has filed (or has obtained extensions with respect to) all material federal, state and local income and franchise tax returns required to be filed through the date of this Agreement, which returns are correct and complete in all material respects, and has timely paid all taxes due thereon, other than those (i) that are being contested in good faith and for which adequate reserves have been established in accordance with generally accepted accounting principles or (ii) that, if not paid, would not have a Material Adverse Effect.

        (hh)     Books and Records .    Each Linn Energy Entity (i) makes and keeps books and records which, in reasonable detail, accurately and fairly reflect the transactions and dispositions of assets and (ii) maintains internal accounting controls sufficient to provide reasonable assurance that (A) transactions are executed in accordance with management's general or specific authorization, (B) transactions are recorded as necessary to permit preparation of its financial statements in conformity with generally accepted accounting principles and to maintain accountability for its assets, (C) access to its assets is permitted only in accordance with management's general or specific authorization and (D) the reported accountability for its assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences.

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        (ii)     Environmental Compliance .    The Linn Energy Entities (i) are in compliance with any and all applicable federal, state and local laws and regulations relating to the protection of human health and safety and the environment or imposing liability or standards of conduct concerning any Hazardous Materials (as defined below) (" Environmental Laws "), (ii) have received all permits required of them under applicable Environmental Laws to conduct their respective businesses, (iii) are in compliance with all terms and conditions of any such permits and (iv) do not have any liability in connection with the release into the environment of any Hazardous Material, except where such noncompliance with Environmental Laws, failure to receive required permits, failure to comply with the terms and conditions of such permits or liability would not, individually or in the aggregate, have a Material Adverse Effect. The term " Hazardous Material " means (A) any "hazardous substance" as defined in the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended, (B) any "hazardous waste" as defined in the Resource Conservation and Recovery Act, as amended, (C) any petroleum or petroleum product, (D) any polychlorinated biphenyl and (E) any pollutant or contaminant or hazardous, dangerous or toxic chemical, material, waste or substance regulated under any other Environmental Law.

        (jj)     Permits .    Each of the Linn Energy Entities has, or at each Closing Date will have, such permits, consents, licenses, franchises, certificates and authorizations of governmental or regulatory authorities (" permits ") as are necessary to own its properties and to conduct its business in the manner described in the Prospectus, subject to such qualifications as may be set forth in the Prospectus and except for such permits which, if not obtained, would not, individually or in the aggregate, have a Material Adverse Effect; except as set forth in the Pricing Prospectus, each of the Linn Energy Entities has, or at each Closing Date will have, fulfilled and performed all its material obligations with respect to such permits which are or will be due to have been fulfilled and performed by such date and no event has occurred that would prevent the permits from being renewed or reissued or which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any impairment of the rights of the holder of any such permit, except for such non-renewals, non-issues, revocations, terminations and impairments that would not, individually or in the aggregate, have a Material Adverse Effect; and, except as described in the Pricing Prospectus, none of such permits contains, or at each Closing Date will contain, any restriction that is materially burdensome to the Linn Energy Entities considered as a whole.

        (kk)     Private Placement .    The sale and issuance of the Existing Investor Units to each Existing Investor were exempt from the registration requirements of the Securities Act, the Rules and Regulations and the securities laws of any state having jurisdiction with respect thereto, and none of the Linn Energy Entities has taken or will take any action that would cause the loss of such exemption.

        (ll)     No Distribution of Other Offering Materials .    The Linn Energy Entities have not distributed and, prior to the later to occur of (i) the First Closing Date and (ii) completion of the distribution of the Units, will not distribute, any prospectus (as defined under the Securities Act) in connection with the offering and sale of the Offered Units other than the Registration Statement, any Preliminary Prospectus, the Prospectus or other materials, if any, permitted by the Securities Act, including Rule 134 of the Rules and Regulations.

        (mm)     Nasdaq Stock Market National Market Listing .    The Units have been approved for listing on the Nasdaq Stock Market Inc.'s National Market, subject only to official notice of issuance.

        (nn)     Investment Company; Public Utility Holding Company .    None of the Linn Energy Entities is now, and after the sale of the Offered Units to be sold by the Company hereunder and the application of the net proceeds from such sale as described in the Pricing Prospectus under the caption "Use of Proceeds" will be, (i) an "investment company" or a company "controlled by" an "investment company" within the meaning of the Investment Company Act of 1940, as amended or (ii) a "public utility company," a "holding company" or a "subsidiary company" of a "holding company" or an "affiliate" thereof, under the Public Utility Holding Company Act of 1935, as amended.

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        (oo)     Brokers .    Except as described in the Pricing Prospectus, there are no contracts, agreements or understandings between any Linn Energy Entity and any person that would give rise to a valid claim against any Linn Energy Entity or any Underwriter for a brokerage commission, finder's fee or other like payment in connection with this offering of the Offered Units.

        (pp)     Market Stabilization .    The Company has not taken, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, under the Exchange Act or otherwise, stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Offered Units.

        (qq)     Directed Unit Sales .    None of the Directed Units distributed in connection with the Directed Unit Program (each as defined in Section 4 hereof) will be offered or sold outside the United States. The Linn Energy Entities have not offered, or caused the Underwriters to offer, Units to any person pursuant to the Directed Unit Program with the specific intent to unlawfully influence (i) a customer or supplier of the Linn Energy Entities, to alter the customer's or supplier's level or type of business with the Linn Energy Entities, or (ii) a trade journalist or publication to write or publish favorable information about the Linn Energy Entities or their operations.

        2.     REPRESENTATIONS AND WARRANTIES OF QUANTUM .    Quantum represents and warrants to each of the Underwriters as follows:

        (a)     Accuracy of Information .    All information with respect to Quantum furnished in writing by Quantum to the Company and included in the Registration Statement and the Pricing Prospectus did not as of the Applicable Time contain an untrue statement of material fact. Quantum agrees that the following information was furnished in writing to the Company specifically for inclusion in the Registration Statement and the Pricing Prospectus: (1) the fifth paragraph under the heading "Our LLC Structure" in the Pricing Prospectus; (2) footnotes one and three to the table under the heading "Security Ownership of Certain Beneficial Owners and Management" in the Pricing Prospectus; and (3) the information regarding Quantum included under the heading "Certain Relationships and Related Party Transactions—Stakeholders' Agreement" in the Pricing Prospectus.

        (b)     Ownership of Units .    Assuming no purchase by the Underwriters of Option Units on the First Closing Date (as defined in Section 3 of this Agreement), at the First Closing Date, after giving effect to the transactions contemplated by the Stakeholders' Agreement, (i) Quantum will beneficially own [10,914,228] Units; and (ii) Clark Partners I, L.P., Kings Highway Investments, LLC and Wauwinet Energy Partners, LLC will beneficially own [281,037] Units in the aggregate.

        (c)     Authority and Authorization .    At the First Closing Date and the Second Closing Date, all partnership action required to be taken by Quantum or the execution and delivery by Quantum of this Agreement and the consummation of the transactions contemplated by this Agreement shall have been validly taken.

        3.     PURCHASE, SALE AND DELIVERY OF THE FIRM UNITS .    

        (a)   On the basis of the representations, warranties and covenants herein contained, and subject to the conditions herein set forth, the Company agrees to sell to the Underwriters and each Underwriter agrees, severally and not jointly, to purchase, at a price of $[    •    ] per unit, the number of Firm Units set forth opposite the name of each Underwriter in Schedule I hereof, subject to adjustments in accordance with Section 9 hereof. The respective purchase obligations of the Underwriters with respect to the Firm Units shall be rounded among the Underwriters to avoid fractional Units, as the Underwriters may determine.

        (b)   Payment for and delivery of the Firm Units are to be made at the offices of Andrews Kurth LLP, Houston, Texas, at 9:00 a.m., Houston time, on the third business day after the date of

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this Agreement or at such other time and date not later than five business days thereafter as you and the Company shall agree upon, such time and date being herein referred to as the " First Closing Date ." As used herein, " business day " means a day on which The Nasdaq National Market is open for trading and on which banks in New York, New York are open for business and are not permitted by law or executive order to be closed. On the First Closing Date, the Company shall cause its transfer agent to deposit as original issue the Firm Units pursuant to the Full Fast Delivery Program of The Depository Trust Company (" DTC ") for the account of each Underwriter against payment to or upon the order of the Company of the purchase price by wire transfer in immediately available funds.

        (c)   In addition, on the basis of the representations and warranties herein contained and subject to the terms and conditions herein set forth, the Company hereby grants an option to the several Underwriters to purchase the Option Units at the price per unit as set forth in the first paragraph of this Section 3. The option granted hereby may be exercised in whole or in part by giving written notice (i) at any time before the Closing Date or (ii) only once thereafter within 30 days after the date of this Agreement, by you to the Company setting forth the number of Option Units as to which the several Underwriters are exercising the option, the names and denominations in which the Option Units are to be registered and the time and date at which such certificates are to be delivered. The time and date at which certificates for Option Units are to be delivered shall be determined by the Underwriters but shall not be earlier than two nor later than five full business days after the exercise of such option, nor in any event prior to the Closing Date (such time and date being herein referred to as the " Second Closing Date, " and the First Closing Date and the Second Closing Date each referred to as a " Closing Date "). On the Second Closing Date, the Company shall cause its transfer agent to deposit as original issue the Option Units pursuant to the Full Fast Delivery Program of the DTC for the account of each Underwriter against payment to or upon the order of the Company of the purchase price by wire transfer in immediately available funds.

        If the date of exercise of the option is three or more days before the Closing Date, the notice of exercise shall set the Closing Date as the Second Closing Date. The number of Option Units to be purchased by each Underwriter shall be in the same proportion to the total number of Option Units being purchased as the number of Firm Units being purchased by such Underwriter as set forth on Schedule I hereto, adjusted by you in such manner as to avoid fractional Units. The option with respect to the Option Units granted hereunder may be exercised only to cover over-allotments in the sale of the Firm Units by the Underwriters. You may cancel such option at any time prior to its expiration by giving written notice of such cancellation to the Company.

        4.     OFFERING BY THE UNDERWRITERS .    

        It is understood that the several Underwriters are to make a public offering of the Firm Units as soon as the Underwriters deem it advisable to do so. The Firm Units are to be initially offered to the public at the initial public offering price set forth in the Prospectus. The Underwriters may from time to time thereafter change the public offering price and other selling terms. To the extent, if at all, that any Option Units are purchased pursuant to Section 3 hereof, the Underwriters will offer them to the public on the foregoing terms.

        As part of the offering contemplated by this Agreement, Lehman Brothers Inc. has agreed to reserve out of the Firm Units set forth opposite its name on Schedule I to this Agreement, up to [    •    ] Firm Units, for sale to the employees, officers, and directors of the Partnership Entities and other parties associated with the Linn Entities (collectively, the " Directed Unit Participants "), as described in the Prospectus under the heading "Underwriting" (the " Directed Unit Program "). The Firm Units to be sold by Lehman Brothers Inc. pursuant to the Directed Unit Program (the " Directed Units ") will be sold by Lehman Brothers Inc. pursuant to this Agreement at the public offering price. Any Directed Units not orally confirmed for purchase by any Directed Unit Participants by 8:00 A.M.

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New York City time on the business day following the date on which this Agreement is executed will be offered to the public by Lehman Brothers Inc. upon the terms and conditions set forth in the Prospectus. Under no circumstances will Lehman Brothers Inc. or any Underwriter be liable to the Linn Energy Entities or to any Directed Unit Participants for any action taken or omitted in good faith in connection with such Directed Unit Program. It is further understood that any Firm Units which are not purchased by Directed Unit Participants will be offered by Lehman Brothers Inc. to the public upon the terms and conditions set forth in the Pricing Prospectus.

        5.     COVENANTS OF THE LINN ENERGY ENTITIES AND THE UNDERWRITERS .    

        Each of the Linn Energy Entities, jointly and severally, covenants and agrees with the several Underwriters that:

        (a)     Preparation of Pricing Prospectus, Prospectus and Registration Statement .    The Company will (i) if the procedure in Rule 430A of the Rules and Regulations is followed, prepare and timely file with the Commission under Rule 424(b) of the Rules and Regulations a Prospectus in a form approved by the Underwriters containing information previously omitted at the time of effectiveness of the Registration Statement in reliance on Rule 430A of the Rules and Regulations; (ii) not file any amendment to the Registration Statement or supplement to the Pricing Prospectus or the Prospectus of which the Underwriters shall not previously have been advised and furnished with a copy or to which the Underwriters shall have reasonably objected (unless, in the latter case, the Company is advised by counsel that it is required by law to make such filing) in writing or which is not in compliance with the Rules and Regulations and (iii) to file promptly all material required to be filed by the Company with the Commission pursuant to Rule 433(d) under the Securities Act.

        (b)     Free Writing Prospectus .    The Company, without the prior consent of RBC Capital Markets Corporation or Lehman Brothers Inc., has not made and will not make any offer relating to the Offered Units that would constitute a "free writing prospectus" as defined in Rule 405 under the Securities Act; each Underwriter severally agrees that such Underwriter shall not include any "issuer information" (as defined in Rule 433) in any "free writing prospectus" (as defined in Rule 405) used or referred to by such Underwriter without the prior consent of the Company (any such issuer information with respect to whose use the Company has given its consent, " Permitted Issuer Information "); provided that (i) no such consent shall be required with respect to any such issuer information contained in any document filed by the Company with the Commission prior to the use of such free writing prospectus and (ii) "issuer information," as used in this Section 5(b), shall not be deemed to include information prepared by or on behalf of such Underwriter on the basis of or derived from issuer information; any such Permitted Issuer Information is listed on Schedule II(a) or Schedule II(b) hereto. The Company has complied and will comply with the requirements of Rule 433 under the Securities Act applicable to any Issuer Free Writing Prospectus, including timely filing with the Commission or retention where required and legending. The Company represents that it has satisfied and agrees that it will satisfy the conditions under Rule 433 under the Securities Act to avoid a requirement to file with the Commission any electronic road show. The Company agrees that if at any time following issuance of an Issuer Free Writing Prospectus any event occurred or occurs as a result of which such Issuer Free Writing Prospectus would conflict with the information in the Registration Statement, the Pricing Prospectus or the Prospectus or would i