Exhibit 10.5

THIRD AMENDMENT

DATED AS OF FEBRUARY 19, 2013

TO THE MARKETING AGENT AGREEMENT

DATED AS OF MARCH 13, 2006, AS AMENDED MARCH 24, 2008 AND

JULY 30, 2012

AMENDMENT AGREEMENT (the “Amendment”) dated as of February 19, 2013 between ALPS
DISTRIBUTORS, INC. (“ALPS”), UNITED STATES COMMODITY FUNDS LLC, formerly
Victoria Bay Asset Management, LLC (“USCF”), and UNITED STATES OIL FUND, LP
(“USOF”).

WITNESSETH

The parties have previously entered into that certain Marketing Agent Agreement
dated as of March 13, 2006, as amended on March 24, 2008 and July 30, 2012 (the
“Agreement”). The parties have agreed to amend the Agreement in accordance with
the terms of this Amendment.

NOW, THEREFORE, in consideration of the mutual agreements herein contained,
ALPS, USCF and USOF hereby acknowledge and agree as follows:

1. Amendment to the Agreement. Upon execution of this Amendment by ALPS, USCF
and USOF, the Agreement shall be hereby amended as follows:

(a) Section 4.3 of the Agreement, “Marketing Agent Fee” shall be amended by
adding the following:

In no event will the Marketing Agent Fee exceed 10% of the gross proceeds of the
Fund’s offering.

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IN WITNESS WHEREOF, the parties have caused this Amendment to be executed by
their respective officers or authorized representatives as of the day and year
first above written.

 

UNITED STATES COMMODITY FUNDS LLC By:  

/s/ Howard Mah

  Name:   Howard Mah   Title:   Management Director UNITED STATES OIL FUND, LP  
By:   United States Commodity Funds LLC, as General Partner     By:  

/s/ Howard Mah

      Name:   Howard Mah       Title:   Management Director ALPS DISTRIBUTORS,
INC By:  

/s/ Thomas A. Carter

  Name:   Thomas A. Carter   Title:   President

 

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