WAIVER

Exhibit 10.20

WAIVER

This WAIVER (this “Waiver”) is made this 19^th day of March 2010, by and among SERVICESOURCE INTERNATIONAL, LLC, a Delaware limited liability company (“Borrower”), WELLS FARGO CAPITAL FINANCE, INC. (formerly known as Wells Fargo Foothill, Inc.), as administrative agent (“Agent”), and the undersigned parties constituting all the Lenders party, as of the date hereof, to that certain Amended and Restated Credit Agreement dated April 29, 2008 by and among Borrower, Agent and the Lenders (as amended, restated, extended, renewed, replaced or otherwise modified from time to time, the “Credit Agreement”; all capitalized terms used herein shall have meanings defined for such terms in the Credit Agreement unless otherwise defined herein).

WITNESSETH:

WHEREAS, pursuant to Section 2.4(c)(iv) of the Credit Agreement, Borrower is required to prepay the Obligations in an amount equal to 25% of its Excess Cash Flow for its fiscal year ended on December 31, 2009 (the “2009 Fiscal Year”);

WHEREAS, Borrower has requested that the Lenders waive the Excess Cash Flow prepayment requirement for the 2009 Fiscal Year and the Lenders are willing to provide such a waiver, as set forth herein.

NOW, THEREFORE, in consideration of the premises and the agreements herein contained, the parties hereto agree as follows:

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IN WITNESS WHEREOF, the parties hereto have caused this Waiver to be duly executed and delivered by their respective officers thereunto duly authorized as of the date first written above,

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Exhibit “A”

ACKNOWLEDGEMENT BY GUARANTOR

Dated as of March 19, 2010

In order to induce the Lender Group to execute the foregoing Waiver (the “Waiver”), with respect to that certain Amended and Restated Credit Agreement (as amended, restated, extended, renewed, replaced or otherwise modified from time to time, the “Credit Agreement”), dated as of April 29, 2008, among ServiceSource International, LLC, the Lenders and Wells Fargo Capital Finance, Inc., as administrative agent for the Lenders, the undersigned hereby represents, warrants and agrees that the undersigned has reviewed and approved the Waiver and that nothing contained therein shall diminish, alter, amend or otherwise affect the undersigned’s obligations under the Guaranty or any other Loan Document executed by it in connection with the Credit Agreement. The undersigned further confirms that each Loan Document executed by it shall continue in full force and effect and agrees that it shall continue to be obligated under each such Loan Document in accordance with the terms thereof. The undersigned further confirms that it has no defense, counterclaim or offset right whatsoever with respect to its obligations under the Loan Documents. Unless otherwise defined, capitalized terms set forth in this Acknowledgment by Guarantor shall have the meaning defined for such term in the Credit Agreement.

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