FIRST AMENDMENT TO AMERICAN CAPITAL, LTD. LOCK UP AGREEMENT

Exhibit 10.60

FIRST AMENDMENT TO AMERICAN CAPITAL, LTD. LOCK UP AGREEMENT

This FIRST AMENDMENT, dated as of January 28, 2010 (this “First Amendment”), amends the Lock Up Agreement, dated as of November 20, 2009 (the “Lock Up”), by and among American Capital, Ltd., a Delaware corporation (the “Company”), and each of the creditors party thereto (the “Consenting Creditors”). Capitalized terms not otherwise defined herein shall have the meanings ascribed to such terms in the Lock Up.

RECITALS

WHEREAS, pursuant to the Lock Up, the Consenting Creditors have agreed to implement a restructuring and reorganization of the Company pursuant to the terms set forth in the Term Sheet and the Private/ Public Terms;

WHEREAS, the Company has requested that the Majority Consenting Creditors enter into this First Amendment on the terms and conditions set forth herein;

NOW, THEREFORE, in consideration of the premises and the mutual covenants and agreements set forth herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties agree as follows:

1. Amendment to Section 4. Section 4 is hereby amended as follows:

(i) in Section 4(ii), by deleting both occurrences of the date “January 15, 2010” and replacing them with “March 15, 2010” and by deleting the date “January 31, 2010” and replacing it with “March 31, 2010”.

(ii) in Section 4(iii)(2), by deleting the date “March 15, 2010” and replacing it with “May 15, 2010” and by deleting the date “March 31, 2010” and replacing it with “May 31, 2010”.

(iii) in Section 4(iii)(3), by deleting the date “March 31, 2010” and replacing it with “May 31, 2010”.

2. Effectiveness. This First Amendment shall not become effective unless and until it has been duly executed and delivered by the Company and the Majority Consenting Creditors.

3. Continuing Effect; No Other Amendments. Except as expressly amended hereby, all of the terms and provisions of the Lock Up are and shall remain in full force and effect. The amendments contained herein shall not constitute an amendment or waiver of any other provision of the Lock Up or for any purpose except as expressly set forth herein.

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4. Counterparts. This First Amendment may be executed in one or more counterparts, each of which shall be deemed an original and all of which shall constitute one and the same First Amendment. Delivery of an executed signature page of this First Amendment by facsimile shall be as effective as delivery of a manually executed signature page of this First Amendment.

5. Severability. Any provision of this First Amendment which is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof or affecting the validity or enforceability of such provision in any other jurisdiction.

6. Headings. The headings of the sections and subsections of this First Amendment are inserted for convenience only and shall not affect the interpretation hereof.

7. No Solicitation. This First Amendment is not and shall not be deemed to be a solicitation of votes for the Plan. In addition, this First Amendment does not constitute an offer to issue or sell securities to any person, or the solicitation of an offer to acquire or buy securities, in any jurisdiction where such offer or solicitation would be unlawful.

8. GOVERNING LAW. THIS FIRST AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK APPLICABLE TO CONTRACTS MADE AND TO BE PERFORMED ENTIRELY WITHIN THAT STATE.

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IN WITNESS WHEREOF, each of the Parties has caused this First Amendment to be executed and delivered by its duly authorized officer as of the date first above written.