TRADEMARK LICENSE AGREEMENT

Exhibit 10.3

TRADEMARK LICENSE AGREEMENT

THIS TRADEMARK LICENSE AGREEMENT (this “ Agreement ”), is made and effective as of the 9 ^th day of November, 2004 (the “Effective Date”), between Natural Gas Partners, L.L.C., a Texas limited liability company (“ Licensor ”), and NGP Capital Resources Company , a Maryland corporation (“ Licensee ”) (each a “party” and collectively, the “parties”).

1.01 “ Licensed Trademarks ” means the trade names “NATURAL GAS PARTNERS” and “NGP.”

2.01 License: Subject to the terms, conditions, and limitations set forth in this Agreement, Licensor hereby grants to Licensee, and Licensee hereby accepts from Licensor, a personal, non-exclusive, royalty-free right and license to use the Licensed Trademarks solely and exclusively as an element of Licensee’s own company name and in connection with Licensee’s business as a business development company under the Investment Company Act of 1940 managed by NGP Investment Advisor, L.P., a Delaware limited partnership (the “Advisor”), pursuant to the terms of the Investment Advisory Agreement dated as of November 9, 2004 (the “Advisory Agreement”). Except as provided above, neither Licensee nor any affiliate, owner, director, officer, employee, or agent thereof will otherwise use the Licensed Trademarks or any derivatives thereof without the prior express written consent of Licensor in its sole and absolute discretion. All rights not expressly granted to Licensee hereunder will remain the property of Licensor.

2.02 Licensor’s Use: Nothing in this Agreement will preclude Licensor, its affiliates, or any of their respective successors or assigns from using or permitting other entities to use the Licensed Trademarks whether or not such entity directly or indirectly competes or conflicts with Licensee’s business in any manner.

3.01 Ownership: Licensee acknowledges and agrees that Licensor is the owner of all right, title, and interest in and to the Licensed Trademarks, and all such right, title, and interest will remain with the Licensor. Licensee will not otherwise contest, dispute, or challenge Licensor’s right, title, and interest in and to the Licensed Trademarks.

3.02 Goodwill: All goodwill and reputation generated by Licensee’s use of the Licensed Trademarks will inure to the benefit of Licensor. Licensee will not by any act or omission use the Licensed Trademarks in any manner that disparages or reflects adversely on Licensor or its business or reputation. Except as expressly provided herein, neither party may use any trademark or service mark of the other party without that party’s prior written consent, which consent will be given in that party’s sole discretion.

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4.01 Specifications: In order to preserve the inherent value of the Licensed Trademarks, Licensee agrees to use reasonable efforts to ensure that it maintains the quality of the services offered under the Licensed Trademarks at least equal to the standards prevailing in the operations of Licensor’s business under the Licensed Trademarks as of the date of this Agreement. Licensee further agrees to use the Licensed Trademarks in accordance with such quality standards as may be reasonably established by Licensor and communicated to Licensee from time to time in writing, or as may be agreed to by Licensor and Licensee from time to time in writing.

4.02 Compliance with Applicable Laws: Licensee agrees that the business operated by it in connection with the Licensed Trademarks will comply with all laws, rules, regulations, and requirements of any governmental body as may be applicable to the operation, advertising and promotion of the business.

5.01 Indemnification and Warranties: Licensor assumes no liability to Licensee or to third parties with respect to the services rendered by Licensee under the Licensed Trademarks and Licensee will indemnify Licensor against losses incurred by claims of third parties against Licensor involving Licensee’s provision of services under the Licensed Trademarks.

5.02 Notification of Infringement: Licensee will immediately notify Licensor and provide to Licensor all relevant background facts upon becoming aware of (i) any registrations of, or applications for registration of, marks that do or may conflict with the Licensed Trademarks, and (ii) any infringements, imitations, or illegal use or misuse of the Licensed Trademarks.

5.03 Mutual Representations: Each party hereby represents and warrants to the other party as follows:

5.03.01 Such party is duly organized and in good standing as of the Effective Date.

5.03.02 Such party has all necessary capacity, power, and authority to enter into and carry out the provisions of this Agreement. This Agreement has been duly authorized, executed, and delivered by each party and constitutes a valid and binding obligati