UNDERWRITING AGREEMENT

Exhibit 10.1

Execution Version

$250,000,000

MAGELLAN MIDSTREAM PARTNERS, L.P.

6.400% Senior Notes due 2037

UNDERWRITING AGREEMENT

April 12, 2007

W ACHOVIA C APITAL M ARKETS , LLC

C ITIGROUP G LOBAL M ARKETS I NC .

J.P. M ORGAN S ECURITIES I NC .

L AZARD C APITAL M ARKETS LLC

L EHMAN B ROTHERS I NC .

S UN T RUST C APITAL M ARKETS , I NC .

c/o Wachovia Capital Markets, LLC

301 South College Street

Charlotte, North Carolina 28288-0613

c/o Citigroup Global Markets Inc.

388 Greenwich Street

New York, NY 10013

Dear Sirs:

Magellan Midstream Partners, L.P., a Delaware limited partnership (the “ Partnership ”), proposes to issue and sell to the several underwriters named in Schedule 1 hereto (collectively, the “ Underwriters ”) $250,000,000 aggregate principal amount of its 6.400% Senior Notes due 2037 (the “ Notes ”) to be issued pursuant to the terms of an indenture (the “ Original Indenture ”) between the Partnership and U.S. Bank National Association, as trustee (the “ Trustee ”), to be dated as of the Delivery Date (as defined in Section 3 ), as supplemented by the First Supplemental Indenture to be dated as of the Delivery Date (the “ Supplemental Indenture ”). The Original Indenture, as so supplemented, is referred to herein as the “ Indenture .” Wachovia Capital Markets, LLC and Citigroup Global Markets Inc. shall act as representatives (the “ Representatives ”) of the several Underwriters. Capitalized terms used but not defined herein shall have the same meanings given them in the Partnership Agreement (as defined herein).

Magellan GP, LLC, a Delaware limited liability company, serves as the general partner (the “ General Partner ”) of the Partnership. The Partnership is the sole limited partner of Magellan OLP, L.P., a Delaware limited partnership (the “ Operating Partnership ”), and the sole member of Magellan Operating GP, LLC, a Delaware limited liability company (“ OLP GP ”), which serves as the general partner of the Operating Partnership. The Partnership is also the sole limited partner of Magellan Pipeline Company, L.P., a Delaware limited partnership (“ MPL LP ”), Magellan Pipeline Terminals, L.P., a Delaware limited partnership (“ MPT LP ”), and the sole member of Magellan Pipeline GP, LLC, a Delaware limited liability company (“ MPGP LLC ”), which serves as the general partner of MPL LP and MPT LP. Each of Magellan NGL, LLC, a Delaware limited liability company (“ MNGL LLC ”), Magellan Terminals Holdings,

 

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L.P., a Delaware limited partnership (“ MTH LP ”), Magellan Pipelines Holdings, L.P., a Delaware limited partnership (“ MPH LP ”), Magellan Ammonia Pipeline, L.P., a Delaware limited partnership (“ MAP LP ”), and Magellan Asset Services, L.P., a Delaware limited partnership (“ MAS LP ”), is a subsidiary of the Operating Partnership, and is sometimes referred to herein individually as a “ Subsidiary ” and collectively as the “ Subsidiaries .” The Operating Partnership also owns a 50% limited liability company interest in Osage Pipe Line Company, LLC, a Delaware limited liability company (“ Osage ”).

The Partnership, the General Partner, the Operating Partnership, OLP GP, MPL LP, MPT LP, MPGP LLC and the Subsidiaries are sometimes referred to herein individually as a “ Partnership Entity ” and collectively as the “ Partnership Entities .” The Partnership Entities, excluding the General Partner, are sometimes referred to herein collectively as the “ Partnership Group .” The Partnership, the General Partner, the Operating Partnership, OLP GP, MPL LP, MPT LP and MPGP LLC are sometimes referred to herein collectively as the “ Magellan Parties .”

This underwriting agreement (this “ Agreement ”) is to confirm the agreement among the Magellan Parties and the Underwriters concerning the purchase of the Notes from the Partnership by the Underwriters.

Section 1. Representations, Warranties and Agreements of the Partnership Entities .

The Magellan Parties, jointly and severally, represent, warrant and agree that:

(a) Registration . A registration statement on Form S-3 (File No. 333-137166) with respect to certain securities, including the Notes, has (i) been prepared by the Partnership 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 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 any amendment thereto have been delivered by the Partnership to the Representatives. As used in this Agreement:

(i) “ Applicable Time ” means 3:09 p.m. (New York City time) on the date of this Agreement, which the Underwriters have informed the Partnership is a time prior to the time of the first sale of the Notes;

(ii) “ Effective Date ” means any date as of which any part of such registration statement relating to the Notes became, or is deemed to have become, effective under the Securities Act in accordance with the Rules and Regulations;

(iii) “ Issuer Free Writing Prospectus ” means each “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations) prepared by or on behalf of the Partnership or used or referred to by the Partnership in connection with the offering of the Notes, including the final term sheet prepared pursuant to Section 4(b) hereof and attached to this Agreement in Annex 1 hereto;

(iv) “ Preliminary Prospectus ” means any preliminary prospectus relating to the Notes included in such registration statement or filed with the Commission pursuant to

 

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Rule 424(b) of the Rules and Regulations, including any preliminary prospectus supplement thereto relating to the Notes;

(v) “ Pricing Disclosure Package ” means, as of the Applicable Time, the most recent Preliminary Prospectus, together with each Issuer Free Writing Prospectus filed or used by the Partnership on or before the Applicable Time, other than a road show that is an Issuer Free Writing Prospectus under Rule 433 of the Rules and Regulations;

(vi) “ Prospectus ” means the final prospectus relating to the Notes, including any prospectus supplement thereto, as filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations; and

(vii) “ Registration Statement ” means, collectively, the various parts of the registration statement on Form S-3 (File No. 333-137166), each as amended as of the Effective Date for such part, including any Preliminary Prospectus or the Prospectus and all exhibits to such registration statement.

Any reference in this Agreement or the exhibits or annexes hereto to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents incorporated by reference therein pursuant to Form S-3 under the Securities Act as of the date of the Registration Statement, such Preliminary Prospectus or the Prospectus, as the case may be. Any reference to the “ most recent Preliminary Prospectus ” shall be deemed to refer to the latest Preliminary Prospectus included in the Registration Statement or filed pursuant to Rule 424(b) prior to or on the date hereof (including, for purposes hereof, any documents incorporated by reference therein prior to or on the date hereof). Any reference to any amendment or supplement to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any document filed under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), after the date of such Preliminary Prospectus or the Prospectus, as the case may be, and incorporated by reference in such Preliminary Prospectus or the Prospectus, as the case may be; and any reference to any amendment to the Registration Statement shall be deemed to include any periodic or current report of the Partnership filed with the Commission pursuant to Section 13(a) or 15(d) of the Exchange Act after the Effective Date that is incorporated by reference in the Registration Statement. The Commission has not issued any order preventing or suspending the use of any Preliminary Prospectus, the Prospectus or any Issuer Free Writing Prospectus or suspending the effectiveness of the Registration Statement, and no proceeding for such purpose has been instituted or threatened by the Commission. The Commission has not notified the Partnership of any objection to the use of the form of the Registration Statement.

(b) Well-Known Seasoned Issuer . The Partnership was, (i) at the time of filing of the Registration Statement and (ii) at the time of the most recent amendment thereto (whether by post-effective amendment, incorporated report filed pursuant to Section 13 or 15(d) of the Exchange Act, or form of prospectus) for purposes of complying with Section 10(a)(3) of the Securities Act (or, if any such amendment was not made within the time period required by Section 10(a)(3) of the Securities Act, at the date on which such amendment was required), a “well-known seasoned issuer” (as defined in Rule 405 of the Rules and Regulations). The Registration Statement is an “automatic shelf registration statement” (as defined in Rule 405 of the Rules and Regulations) and was filed not earlier than the date that is three years prior to the

 

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Delivery Date. The Partnership was not at the time of initial filing of the Registration Statement and at the earliest time thereafter that the Partnership or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) of the Rules and Regulations) of the Notes, and will not be on the Delivery Date, an “ineligible issuer” (as defined in Rule 405 of the Rules and Regulations).

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

(d) Registration Statement . The Registration Statement did not, as of the Effective Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; and each of the statements made by the Partnership in the Registration Statement and any further amendments to the Registration Statement within the coverage of Rule 175(b) of the Rules and Regulations, including (but not limited to) any statements with respect to future cash distributions of the Partnership or the anticipated ratio of taxable income to distributions was made with a reasonable basis and in good faith; provided that no representation or warranty is made as to information contained in or omitted from the Registration Statement in reliance upon and in conformity with written information furnished to the Partnership through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information is specified in Section 7(e) .

(e) Prospectus . The Prospectus will not, as of its date or on the Delivery Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and each of the statements made or to be made by the Partnership in the Preliminary Prospectus or the Prospectus, as applicable, and any further supplements to the Preliminary Prospectus or the Prospectus within the coverage of Rule 175(b) of the Rules and Regulations, including (but not limited to) any statements with respect to future cash distributions of the Partnership or the anticipated ratio of taxable income to distributions was made with a reasonable basis and in good faith; provided that no representation or warranty is made as to information contained in or omitted from the Prospectus in reliance upon and in conformity with written information furnished to the Partnership through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information is specified in Section 7(e) .

(f) Documents Incorporated by Reference . The documents incorporated by reference in the Registration Statement, any Preliminary Prospectus or the Prospectus, when they were filed with the Commission and on the Delivery Date, conformed and will conform in all

 

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material respects to the requirements of the Exchange Act and the rules and regulations of the Commission thereunder and any further documents filed with the Commission and incorporated by reference in the Registration Statement, any Preliminary Prospectus or the Prospectus, when filed with the Commission and on the Delivery Date, will conform in all material respects to the requirements of the Exchange Act and the rules and regulations of the Commission thereunder. The documents incorporated by reference in the Registration Statement, any Preliminary Prospectus or the Prospectus did not, and any further documents filed and incorporated by reference therein will not, when filed with the Commission and on the Delivery Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

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

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

(i) Each Issuer Free Writing Prospectus . Each Issuer Free Writing Prospectus conformed or will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations on the date of first use, and the Partnership has complied with any filing requirements applicable to such Issuer Free Writing Prospectus pursuant to the Rules and Regulations. The Partnership has not made any offer relating to the Notes that would constitute an Issuer Free Writing Prospectus without the prior written consent of the Representatives, except as set forth on Annex 2 hereto. The Partnership has retained in accordance with the Rules and Regulations all Issuer Free Writing Prospectuses that were not required to be filed pursuant to the Rules and Regulations (it being understood that, as of the date hereof, the Partnership has not retained any Issuer Free Writing Prospectus for the three year period required thereby).

(j) Formation and Qualification of the Magellan Partnerships . Each of the Partnership, the Operating Partnership, MPL LP, MPT LP, MTH LP, MPH LP, MAP LP, MAS LP and Magellan IDR, L.P., a Delaware limited partnership (“ IDR LP ”) has been duly formed and is validly existing in good standing as a limited partnership under the Delaware Revised Uniform Limited Partnership Act (the “ Delaware LP Act ”), has full partnership power and authority necessary to own or hold its properties and assets and to conduct the businesses in which it is engaged, and is duly registered or qualified to do business as a foreign limited

 

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partnership in each jurisdiction set forth opposite its name on Annex 3 hereto, and such jurisdictions constitute all of the jurisdictions, with respect to each of the Partnership, the Operating Partnership, MPL LP, MPT LP, MTH LP, MPH LP, MAP LP, MAS LP and IDR LP, in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so register or qualify would not (i) have a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders’ equity or results of operations of the Partnership Group, taken as a whole, or (ii) subject the limited partners of the Partnership to any material liability or disability.

(k) Formation and Qualification of the Magellan Limited Liability Companies . Each of the General Partner, OLP GP, MPGP LLC, MNGL LLC, Magellan IDR LP, LLC, a Delaware limited liability company (“ IDR LLC ”) and Osage has been duly formed and is validly existing in good standing as a limited liability company under the Delaware Limited Liability Company Act (the “ Delaware LLC Act ”), has full limited liability company power and authority necessary to own or hold its properties and to conduct the businesses in which it is engaged, and is duly registered or qualified to do business as a foreign limited liability company in each jurisdiction set forth opposite its name on Annex 3 hereto, and such jurisdictions constitute all of the jurisdictions, with respect to each of the General Partner, OLP GP, MPGP LLC, MNGL LLC, IDR LLC and Osage, in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so register or qualify would not (i) have a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders’ equity or results of operations of the Partnership Group, taken as a whole, or (ii) subject the limited partners of the Partnership to any material liability or disability.

(l) [Intentionally Omitted.]

(m) Ownership of Interests; Subsidiaries . Other than (i) the General Partner’s ownership of the 1.995% general partner interest in the Partnership, a 100% membership interest in IDR LLC and a 0.001% general partner interest in IDR LP, (ii) the Partnership’s ownership of 100% of the member interests in MPGP LLC, 100% of the member interest of OLP GP, a 99.999% limited partner interest in the Operating Partnership, a 99.999% limited partner interest in each of MPL LP and MPT LP, (iii) OLP GP’s ownership of a 0.001% general partner interest in the Operating Partnership, (iv) MPGP LLC’s ownership of a 0.001% general partner interest in each of MPL LP and MPT LP, (v) the Operating Partnership’s ownership of a 99.999% limited partner interest in each of MAP LP, MTH LP, MPH LP and MAS LP, 100% of the member interests in MNGL LLC and 50% of the member interests in Osage and (vi) MNGL LLC’s ownership of a 0.001% general partner interest in each of MAP LP, MTH LP, MPH LP and MAS LP, none of the Partnership Entities own and, at the Delivery Date, will own, directly or indirectly, any equity of any corporation, partnership, limited liability company, joint venture, association or other entity; and none of these entities, other than the Operating Partnership, MPL LP and MTH LP, is a “ significant subsidiary ” of the Partnership as such term is defined in Rule 405 of the Rules and Regulations.

(n) Ownership of the General Partner Interest in the Partnership . The General Partner is the sole general partner of the Partnership with a 1.995% general partner interest in the Partnership; such general partner interest has been duly and validly authorized and issued in accordance with the agreement of limited partnership of the Partnership (as the same may be

 

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amended or restated on or prior to the Delivery Date, the “ Partnership Agreement ”); and the General Partner owns such general partner interest free and clear of all liens, encumbrances, security interests, equities, charges or claims (collectively, “ Liens ”).

(o) Ownership of the Incentive Distribution Rights and Outstanding Units . As of the Applicable Time and the date of the Prospectus, the Partnership has no limited partner interests issued and outstanding other than the following:

(i) the Incentive Distribution Rights (as defined in the Partnership Agreement) held by IDR LP; and

(ii) 66,546,297 Common Units held by public unitholders,

all of such Incentive Distribution Rights and Common Units and the limited partner interests represented thereby have been duly authorized and validly issued in accordance with the Partnership Agreement and are fully paid (to the extent required under the Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the General Partner owns all of such Incentive Distribution Rights, free and clear of all Liens.

(p) Authority. Each of the Magellan Parties has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder; the Partnership has full right, power and authority to execute and deliver the Notes, the Original Indenture and the Supplemental Indenture and to perform its obligations thereunder (this Agreement, the Notes, the Original Indenture and the Supplemental Indenture, are each referred to herein individually as a “ Debt Document ” and collectively as the “ Debt Documents ”). On the Delivery Date, all corporate, partnership and limited liability company action, as the case may be, required to be taken by the Magellan Parties, or any of their securityholders, partners or members for (i) the authorization, issuance, sale and delivery of the Notes, (ii) the execution and delivery of the Debt Documents and (iii) the consummation of the transactions contemplated by the Debt Documents, shall have been validly taken.

(q) Authorization and Enforceability of the Indenture. The Indenture has been duly qualified under the Trust Indenture Act of 1939, as amended (the “ Trust Indenture Act ”), and as of the Delivery Date, the Indenture will be duly authorized, executed and delivered by the Partnership and will constitute a valid and legally binding agreement of the Partnership enforceable against the Partnership in accordance with its terms, except as enforceability may be limited by the Enforceability Exceptions (as defined in Section 1(cc) herein).

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

(s) Descriptions . Each Debt Document that is described in the Registration Statement, the Pricing Disclosure Package and the Prospectus conforms in all material respects

 

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to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(t) Ownership of OLP GP . The Partnership is the sole member of OLP GP with a 100% member interest in OLP GP; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of OLP GP (as the same may be amended or restated on or prior to the Delivery Date, the “ OLP GP LLC Agreement ”), and is fully paid (to the extent required under the OLP GP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Partnership owns such member interest free and clear of all Liens.

(u) Ownership of MPGP LLC . The Partnership is the sole member of MPGP LLC with a 100% member interest in MPGP LLC; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of MPGP LLC (as the same may be amended or restated on or prior to the Delivery Date, the “ MPGP LLC Agreement ”), and is fully paid (to the extent required under the MPGP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Partnership owns such member interest free and clear of all Liens.

(v) Ownership of the Operating Partnership .

(i) OLP GP is the sole general partner of the Operating Partnership with a 0.001% general partner interest in the Operating Partnership; such general partner interest has been duly authorized and validly issued in accordance with the agreement of limited partnership of the Operating Partnership (as the same may be amended or restated on or prior to the Delivery Date, the “ Operating Partnership Agreement ”); and the OLP GP owns such general partner interest free and clear of all Liens.

(ii) The Partnership is the sole limited partner of the Operating Partnership with a 99.999% limited partner interest in the Operating Partnership; such limited partner interest has been duly authorized and validly issued in accordance with the Operating Partnership Agreement and is fully paid (to the extent required under the Operating Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the Partnership owns such limited partner interest free and clear of all Liens.

(w) Ownership of MNGL LLC . The Operating Partnership is the sole member of MNGL LLC with a 100% member interest in MNGL LLC; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of MNGL LLC (as the same may be amended or restated on or prior to the Delivery Date, the “ MNGL LLC Agreement ”), and is fully paid (to the extent required under the MNGL LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Operating Partnership owns such member interest free and clear of all Liens.

(x) Ownership of the LP Subsidiaries .

(i) MNGL LLC is the sole general partner of each of MAP LP, MAS LP, MPH LP and MTH LP (the “ LP Subsidiaries ”) with a 0.001% general partner interest in

 

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each of the LP Subsidiaries; each such general partner interest has been duly authorized and validly issued in accordance with each of the respective agreements of limited partnership of each of the LP Subsidiaries (as each may be amended and restated on or prior to the Delivery Date, the “ LP Subsidiary Partnership Agreements ”); and MNGL LLC owns each such general partner interest free and clear of all Liens.

(ii) The Operating Partnership is the sole limited partner of each of the LP Subsidiaries with a 99.999% limited partner interest in each of the LP Subsidiaries; each such limited partner interest has been duly authorized and validly issued in accordance with each of the respective LP Subsidiary Partnership Agreements and is fully paid (to the extent required under each of the LP Subsidiary Partnership Agreements) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the Operating Partnership owns each of such limited partner interest free and clear of all Liens.

(y) Ownership of the General Partner . Magellan Midstream Holdings, L.P., a publicly traded Delaware limited partnership (“ MGG ”), is the sole member of the General Partner with a 100% member interest in the General Partner; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of the General Partner (as the same may be amended or restated on or prior to the Delivery Date, the “ GP LLC Agreement ”), and is fully paid (to the extent required under the GP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act).

(z) Ownership of MPL LP and MPT LP .

(i) MPGP LLC is the sole general partner of each of MPL LP and MPT LP with a 0.001% general partner interest in each of MPL LP and MPT LP; each such general partner interest has been duly authorized and validly issued in accordance with the respective agreements of limited partnership of each of MPL LP and MPT LP (as each may be amended or restated on or prior to the Delivery Date, respectively, the “ MPL LP Partnership Agreement ” and the MPT LP Partnership Agreement ); and MPGP LLC owns each such general partner interest free and clear of all Liens.

(ii) The Partnership is the sole limited partner of each of MPL LP and MPT LP with a 99.999% limited partner interest in each of MPL LP and MPT LP; each such limited partner interest has been duly authorized and validly issued in accordance with the MPL LP Partnership Agreement and the MPT LP Partnership Agreement, as applicable, and is fully paid (to the extent required under the MPL LP Partnership Agreement or the MPT LP Partnership Agreement, as applicable) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the Partnership owns each such limited partner interest free and clear of all Liens.

(aa) Ownership of Osage . The Operating Partnership owns a 50% member interest in Osage; such membership interest has been duly authorized and validly issued in accordance with the limited liability company agreement of Osage (as the same may be amended or restated on or prior to the Delivery Date, the “ Osage LLC Agreement ”), and is fully paid (to the extent

 

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required under the Osage LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Operating Partnership owns such member interest free and clear of all Liens.

(bb) Authorization of the Agreement . This Agreement has been duly authorized, executed and delivered by the Magellan Parties.

(cc) Authorization and Enforceability of Other Agreements .

(i) The Partnership Agreement has been duly authorized, executed and delivered and is a valid and legally binding agreement of the General Partner, enforceable against the General Partner in accordance with its terms.

(ii) The Operating Partnership Agreement has been duly authorized, executed and delivered by OLP GP and the Partnership, and is a valid and legally binding agreement of OLP GP and the Partnership, enforceable against OLP GP and the Partnership in accordance with its terms.

(iii) The GP LLC Agreement has been duly authorized, executed and delivered by MGG, and is a valid and legally binding agreement of MGG, enforceable against MGG in accordance with its terms.

(iv) The MPL LP Partnership Agreement has been duly authorized, executed and delivered by MPGP LLC and the Partnership, and is a valid and legally binding agreement of MPGP LLC and the Partnership, enforceable against MPGP LLC and the Partnership in accordance with its terms.

(v) The MNGL LLC Agreement has been duly authorized, executed and delivered by the Operating Partnership, and is a valid and legally binding agreement of the Operating Partnership, enforceable against the Operating Partnership in accordance with its terms.

(vi) Each of the LP Subsidiary Partnership Agreements has been duly authorized, executed and delivered by the Operating Partnership and MNGL LLC and is a valid and legally binding agreement of the Operating Partnership and MNGL LLC, enforceable against the Operating Partnership and MNGL LLC in accordance with its terms.

(vii) The MPGP LLC Agreement has been duly authorized, executed and delivered by the Partnership, and is a valid and legally binding agreement of the Partnership, enforceable against the Partnership in accordance with its terms.

(viii) The Osage LLC Agreement has been duly authorized, executed and delivered by the Operating Partnership and is a valid and legally binding agreement of the Operating Partnership, enforceable against the Operating Partnership in accordance with its terms.

(ix) The MPT LP Partnership Agreement has been duly authorized, executed and delivered by the Partnership and MPGP LLC and is a valid and legally binding

 

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agreement of the Partnership and MPGP LLC, enforceable against the Partnership and MPGP LLC in accordance with its terms.

(x) The OLP GP LLC Agreement has been duly authorized, executed and delivered by the Partnership, and is a valid and legally binding agreement of the Partnership, enforceable against the Partnership in accordance with its terms.

provided that, with respect to each agreement described in Section 1(cc) above, the enforceability thereof may be limited by applicable bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws relating to or affecting the enforcement of creditors’ rights generally and by general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law) (the “ Enforceability Exceptions ”); and provided further , that the indemnity, contribution and exoneration provisions contained in any of such agreements may be limited by applicable laws.

(dd) No Conflicts or Violations . None of the (i) offering, issuance and sale by the Partnership of the Notes, (ii) execution, delivery and performance of the Debt Documents by the Magellan Parties, (iii) consummation of the transactions contemplated by the Debt Documents, or (iv) application of the proceeds from the sale of the Notes as described under “Use of Proceeds” in each of the most recent Preliminary Prospectus and the Prospectus (A) conflicts or will conflict with or constitutes or will constitute a breach or violation of any provision of the certificate of limited partnership or agreement of limited partnership, certificate of formation or limited liability company agreement or operating agreement, or any other organizational documents of any of the Partnership Entities, (B) 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 an event) any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which any of the Partnership Entities is a party or by which any of them or any of their respective properties may be bound, (C) 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 Partnership Entities or any of their assets or properties in a proceeding to which any of them or other property is a party or (D) will result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of any of the Partnership Entities, in the case of clauses (B) , (C)  or (D) , which conflicts, breaches, violations or defaults would have a material adverse effect upon the condition (financial or other), business, prospects, properties, securityholders’ equity or results of operations of the Partnership Group, taken as a whole.

(ee) No Consents . No permit, consent, approval, authorization, order, registration, filing or qualification of or with any court or arbitrator or governmental or regulatory authority (a “ Consent ”) is required for (i) the execution, delivery and performance of each of the Debt Documents, (ii) the issuance and sale of the Notes and compliance by the Magellan Parties with the terms thereof by the Magellan Parties, (iii) the consummation of the transactions contemplated by the Debt Documents ( including the issuance and sale of the Notes), or (iv) the application of the proceeds from the sale of the Notes as described under “Use of Proceeds” in each of the most recent Preliminary Prospectus and the Prospectus except for such Consents (A) as have been, or will be prior to the Delivery Date, obtained under the Securities Act, the Exchange Act and the Trust Indenture Act, (B) as may be required under applicable state securities or “blue sky” laws in connection with the purchase and distribution of the Notes by

 

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the Underwriters, and (C) that, if not obtained or made, would not, individually or in the aggregate, have a material adverse effect on the condition (financial or other), business, assets or results of operations of the Partnership Group, taken as a whole.

(ff) No Sales . No Partnership Entity has sold or issued any securities of the same class as the Notes during the six-month period preceding the date of the Prospectus, including any sales pursuant to Rule 144A under, or Regulations D or S of, the Securities Act other than Notes sold pursuant to the Registration Statement.

(gg) No Material Adverse Change . Neither the General Partner nor any member of the Partnership Group has sustained, since the date of the latest audited financial statements included or incorporated by reference in the most recent Preliminary Prospectus, any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth or contemplated in the most recent Preliminary Prospectus; and, since such date, (i) there has not been any change in the capitalization or long-term debt of the General Partner or the capitalization or consolidated long-term debt of the Partnership Group, taken as a whole, or (ii) any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, consolidated financial position, securityholders’ equity, capitalization, results of operations, business or prospects of the Partnership Group, taken as a whole, otherwise than as set forth or contemplated in the most recent Preliminary Prospectus.

(hh) Financial Statements . The historical financial statements (including the related notes and supporting schedules) included or incorporated by reference in the Registration Statement, the most recent Preliminary Prospectus, and the Prospectus (and any amendment or supplement thereto) comply as to form in all material respects with the requirements of Regulation S-X under the Securities Act and the Exchange Act and present fairly in all material respects the financial position, results of operations and cash flows of the entities purported to be shown thereby on the basis stated therein at the respective dates or for the respective periods to which they apply, and have been prepared in accordance with generally accepted accounting principles consistently applied throughout the periods involved. Any summary selected historical financial information set forth in the Registration Statement, the most recent Preliminary Prospectus and the Prospectus (and any amendment or supplement thereto) is accurately presented in all material respects and prepared on a basis consistent with the audited and unaudited historical consolidated financial statements from which it has been derived.

(ii) Independent Registered Public Accounting Firm . Ernst & Young LLP, who have certified certain financial statements of the General Partner and the Partnership Group, and whose reports are included and incorporated by reference in the Registration Statement, the most recent Preliminary Prospectus and the Prospectus (and any amendment or supplement thereto) and who have delivered the letter referred to in Section 6(g) hereof, are and have been, during the periods covered by the financial statements on which they reported, an independent registered public accounting firm with respect to the General Partner and the Partnership Group as required by the Securities Act and the Rules and Regulations and the Public Company Accounting Oversight Board (United States) (the “ PCAOB ”).

 

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(jj) Title to Properties . The General Partner and each member of the Partnership Group have good and indefeasible title to all real property and good title to all personal property owned by them, in each case free and clear of all liens, claims, security interests, encumbrances and other defects, except (i) such as are described in the most recent Preliminary Prospectus and the Prospectus or (ii) such as do not materially affect the value of such property taken as a whole and do not materially interfere with the use made and proposed to be made of such property taken as a whole as described in the most recent Preliminary Prospectus and the Prospectus; provided that, with respect to title to pipeline rights-of-way, the Magellan Parties represent only that none of MPH LP, MAP LP, MPL LP or, to their knowledge, Osage, has received any actual notice or claim from any owner of land upon which its pipeline is located that any of such entities, as applicable, does not have sufficient title to enable it to use and occupy the pipeline rights-of-way as they are used and occupied as described in the most recent Preliminary Prospectus and the Prospectus and which constitute valid claims or which have not been satisfied by the applicable parties that will have a material adverse effect on the condition (financial or other), business, prospects, properties or results of operations of the Partnership Group, taken as a whole. All assets held under lease or license by the members of the Partnership Group are held under valid, subsisting and enforceable leases or licenses, with such exceptions (i) as are not material and do not interfere with the use made and proposed to be made of such assets as they have been used as described in the most recent Preliminary Prospectus and the Prospectus or (ii) that would not have a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders’ equity or results of operations of the Partnership Group, taken as a whole.

(kk) Insurance . Each of the Partnership Entities carries, or is covered by, insurance in such amounts and covering such risks as is adequate for the conduct of its business and the value of their respective properties and as is customary for businesses engaged in similar businesses in similar industries, and none of the Partnership Entities has received notice of cancellation or non-renewal of such insurance.

(ll) Intellectual Property . Each of the Partnership Entities owns or possesses adequate rights to use all patents, patent applications, trademarks, service marks, trade names, trademark registrations, service mark registrations, copyrights and licenses necessary for the conduct of its business and none of the Partnership Entities is aware of any claim to the contrary or any challenge by any other person to the rights of any of the Partnership Entities with respect to the foregoing.

(mm) No Legal Proceedings . Except as described in the most recent Preliminary Prospectus and the Prospectus, there are no legal or governmental proceedings pending to which any of the Partnership Entities is a party or of which any property or assets of any of the Partnership Entities is the subject that are required to be described in the Registration Statement, the most recent Preliminary Prospectus and the Prospectus and that are not described as required; and to the best knowledge of the Partnership Entities, no such proceedings are threatened by governmental authorities or by others.

(nn) Adequate Disclosure. There are no agreements, contracts or other documents which are required to be described in the Prospectus or filed as exhibits to the Registration Statement by the Securities Act or by the Rules and Regulations thereunder which have not been described in the Prospectus or filed as exhibits to the Registration Statement.

 

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(oo) Related Party Transactions . No relationship, direct or indirect, exists between or among any member of the Partnership Group on the one hand, and the securityholders, customers or suppliers of any member of the Partnership Group, the directors or officers of the General Partner, or any affiliate of a member of the Partnership Group, on the other hand, which is required to be described in the Registration Statement, the most recent Preliminary Prospectus and the Prospectus, which is not so described; and no Partnership 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 Partnership Entity.

(pp) No Labor Disputes . Except as described in the most recent Preliminary Prospectus and the Prospectus, no labor disturbance by the employees of any member of the Partnership Group (and to the extent they perform services on behalf of any of any member of the Partnership Group, employees of the general partner of MGG), exists or, to the knowledge of the Partnership Entities, is imminent or threatened, which might be expected to have a material adverse effect on the general affairs, management, consolidated financial position, securityholders’ equity, results of operations, business or prospects of the Partnership Group, taken as whole.

(qq) Employee Benefit Matters . The Partnership and the General Partner are in compliance in all material respects with all presently applicable provisions of the Employee Retirement Income Security Act of 1974, as amended, including the regulations and published interpretations thereunder (“ ERISA ”); no “reportable event” (as defined in ERISA) has occurred with respect to any “pension plan” (as defined in ERISA) for which the General Partner or the Partnership would have any liability; neither the Partnership nor the General Partner has incurred nor does either expect to incur liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any “pension plan” or (ii) Sections 412 or 4971 of the Internal Revenue Code of 1986, as amended, including the regulations and published interpretations thereunder (the “ Code ”); and each “pension plan” for which the General Partner or the Partnership would have any liability that is intended to be qualified under Section 401(a) of the Code has been determined by the Internal Revenue Service to be so qualified and nothing has occurred, whether by action or by failure to act, which could reasonably be expected to cause the loss of such qualification.

(rr) Tax Returns . Each of the Partnership Entities has filed (or has obtained extensions with respect to) all material tax returns required to be filed through the date hereof, which returns are complete and correct in all material respects, and has paid all taxes shown to be due pursuant to such returns, other than those (i) which, if not paid, would not have a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders’ equity or results of operations of the Partnership Group, taken as a whole, or (ii) which are being contested in good faith. No tax deficiency has been determined adversely to any Partnership Entity which has had (nor does the Partnership have any knowledge of any tax deficiency which, if determined adversely to any Partnership Entity, might have) a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders’ equity or results of operations of the Partnership Group, taken as a whole.

(ss) No Changes . Since the date as of which information is given in the most recent Preliminary Prospectus through the date hereof, and except as may otherwise be disclosed in the

 

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most recent Preliminary Prospectus, neither the General Partner nor any member of the Partnership Group has (i) issued or granted any securities, (ii) incurred any material liability or obligation, direct or contingent, other than liabilities and obligations which were incurred in the ordinary course of business, (iii) entered into any transaction not in the ordinary course of business or (iv) declared or paid any distributions other than to another member of the Partnership Group.

(tt) Books and Records . The Partnership Entities (i) make and keep accurate books and records and (ii) maintain internal accounting controls which provide reasonable assurance that (A) transactions are executed in accordance with management’s authorization, (B) transactions are recorded as necessary to permit preparation of the Partnership’s consolidated financial statements and to maintain accountability for the Partnership’s consolidated assets, (C) access to its assets is permitted only in accordance with management’s authorization and (D) the reported accountability for its assets is compared with existing assets at reasonable intervals.

(uu) No Violations or Defaults . None of the Partnership Entities (i) is in violation of its certificate of limited partnership or agreement of limited partnership, certificate of formation or limited liability company agreement, certificate of incorporation or bylaws or other organizational or governing documents; (ii) is in breach or default in any respect, and no event has occurred which, with notice or lapse of time or both, would constitute such a breach or default, in the due performance or observance of any term, covenant or condition contained in any material 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, (iii) is in violation of any law, ordinance, governmental rule, regulation or court decree to which it or its property or assets may be subject or (iv) has failed to obtain any license, permit, certificate, franchise or other governmental authorization or permit necessary to the ownership of its property or to the conduct of its business, except in the case of clauses (ii) , (iii)  and (iv)  as would not have a material adverse effect on the condition (financial or other), business, assets or results of operations of the Partnership Group, taken as a whole, or could materially impair the ability of any of the Magellan Parties to perform their respective obligations, if any, under this Agreement.

(vv) FCPA . No Partnership Entity, nor any director, officer, agent, employee or other person associated with or acting on behalf of any Partnership Entity has used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977, as amended; or made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment.

(ww) Environmental Compliance . Except as described in the most recent Preliminary Prospectus and the Prospectus, none of the Partnership Entities has violated any environmental, safety, health or similar law or regulation applicable to its business relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“ Environmental Laws ”), or lacks any permits, licenses or other approvals required of them under applicable Environmental Laws to own, lease or operate their properties and conduct their business as described in the most recent Preliminary Prospectus or is violating any terms and conditions of any such permit, license or approval, which in each case would

 

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have a material adverse effect on the condition (financial or other), business, assets or results of operations of the Partnership Group, taken as a whole.

(xx) Investment Company . Neither the General Partner nor any member of the Partnership Group is, or, as of the Delivery Date after giving effect to the offer and sale of the Notes by the Partnership and the application of the net proceeds as described in the most recent Preliminary Prospectus and the Prospectus, will be, an “ investment company ” as defined in the Investment Company Act of 1940, as amended.

(yy) Certificates . Each certificate signed by or on behalf of any Partnership Entity and delivered to the Underwriters or counsel for the Underwriters pursuant to this Agreement shall be deemed to be a representation and warranty by such Partnership Entity to the Underwriters as to the matters covered thereby.

(zz) Compliance with Sarbanes-Oxley . The Partnership is in compliance in all material respects with all provisions of the Sarbanes-Oxley Act of 2002.

(aaa) Statistical Data . The statistical and market-related data included in the most recent Preliminary Prospectus and the Registration Statement are based on or derived from sources which the Partnership Entities believe to be reliable and accurate.

(bbb) Disclosure Controls and Procedures . The Partnership has established and maintains disclosure controls and procedures (as such term is defined in rule 13a-15 under the Exchange Act), which (i) are designed to ensure that material information relating to the Partnership, including its consolidated subsidiaries, is made known to the Partnership’s principal executive officer and its principal financial officer by others within those entities, particularly during the periods in which the periodic reports required under the Exchange Act are being prepared, (ii) have been evaluated for effectiveness as of December 31, 2006, and (iii) are effective in all material respects to perform the functions for which they were established.

(ccc) Internal Control Over Financial Reporting . Since the date of the most recent audited balance sheet of the Partnership and its consolidated subsidiaries reviewed or audited by Ernst & Young LLP and the audit committee of the board of directors of the General Partner, (i) the Partnership has not been advised of (A) any significant deficiencies in the design or operation of internal control over financial reporting that could adversely affect the ability of the Partnership and each of its subsidiaries to record, process, summarize and report financial data, or any material weaknesses in internal control over financial reporting and (B) any fraud, whether or not material, that involves management or other employees who have a significant role in the internal control over financial reporting of the Partnership and each of its subsidiaries, and (ii) since that date, there have been no changes in internal control over financial reporting, including any corrective actions with regard to significant deficiencies and material weaknesses, that has materially affected, or is reasonably likely to materially affect, the Partnership’s internal control over financial reporting.

(ddd) No Distribution of Offering Materials . None of the Partnership Entities has distributed and, prior to the later to occur of the Delivery Date and completion of the distribution of the Notes, will distribute any offering material in connection with the offering and sale of the Notes other than any Preliminary Prospectus, the Prospectus, any Issuer Free

 

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Writing Prospectus to which the Representatives have consented in accordance with Sections 1(i) or 4(f) and any Issuer Free Writing Prospectus set forth in Annex 2 hereto.

Section 2. Purchase of the Notes by the Underwriters .

On the basis of the representations and warranties c