AMENDMENT NO. 4 TO THE AMENDED AND RESTATED DECLARATION OF TRUST AND TRUST AGREEMENT OF POWERSHARES DB COMMODITY INDEX TRACKING FUND

Exhibit 4.1

AMENDMENT NO. 4 TO THE

AMENDED AND RESTATED

DECLARATION OF TRUST AND TRUST AGREEMENT

OF

POWERSHARES DB COMMODITY INDEX TRACKING FUND

This Amendment No. 4 (“Amendment No. 4”) to the Amended and Restated Declaration of Trust and Trust Agreement dated as of December 1, 2005 (the “Declaration of Trust”) of PowerShares DB Commodity Index Tracking Fund (the “Trust”) by and among DB Commodity Services LLC (the “Managing Owner”), Wilmington Trust Company and the Unitholders, from time-to-time thereunder.

WHEREAS, the Managing Owner has deemed it advisable for the Trust to amend and replace the definition of “Index Commodities” as defined in the Declaration of Trust;

WHEREAS, the Managing Owner wishes to amend the Declaration of Trust pursuant to Section 11.1(b)(iii) thereof to give effect to the adoption of a new definition of “Index Commodities” effective as of October 19, 2009.

NOW, THEREFORE, in consideration of the premises and of other good and valuable consideration, the receipt and sufficiency of all of which are hereby acknowledged, the Declaration of Trust is amended as follows:

“‘Index Commodities’ means the underlying Commodities which comprise the Deutsche Bank Liquid Commodity Index–Optimum Yield Diversified Excess Return™ from time to time, as described in the Prospectus.”

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IN WITNESS WHEREOF, this Amendment No. 4 has been executed for and on behalf of the undersigned as of the 30^th day of September, 2009.

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