Exhibit 4
Joint Filing Agreement
In accordance with Rule 13d-1(k)(1)(iii) under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree by and among themselves to the joint filing on behalf of them of a Statement on Schedule 13D and that this Agreement be included as an Exhibit to such filing. The undersigned further agree that any and all amendments to such Statement on Schedule 13D may be filed on behalf of each of the undersigned without the necessity of filing additional joint filing agreements. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of the information concerning it contained in such Statement on Schedule 13D or in any such joint amendment thereto, but shall not be responsible for the completeness and accuracy of the information concerning the others, except to the extent that it knows or has reason to believe that such information is inaccurate. This Agreement may be executed in any number of counterparts, each of which shall be deemed an original and all of which together constitute one instrument.
[Remainder of Page Intentionally Left Blank]
IN WITNESS WHEREOF, the undersigned hereby execute this Agreement as of this 9th day of December, 2011.
| Statoil ASA | ||
By: | /s/ IRENE RUMMELHOFF | |
Name: | Irene Rummelhoff | |
Title: | Attorney-in-Fact | |
| Statoil Petroleum AS | ||
By: | /s/ JEFFREY C. ZARUBA | |
Name: | Jeffrey C. Zaruba | |
Title: | Attorney-in-Fact | |
| Statoil International Holding AS | ||
By: | /s/ JEFFREY C. ZARUBA | |
Name: | Jeffrey C. Zaruba | |
Title: | Attorney-in-Fact | |
| Statoil Investment Americas AS | ||
By: | /s/ HELGE HALDORSEN | |
Name: | Helge Haldorsen | |
Title: | Vice President — Strategy and Director | |
| Statoil E&P Americas LP | ||
| By: Statoil Americas Investments LLC, its general partner | ||
By: | /s/ JEFFREY C. ZARUBA | |
Name: | Jeffrey C. Zaruba | |
Title: | Treasurer and Assistant Secretary | |
| Statoil USA Properties Inc. | ||
By: | /s/ ANDREW BYRON WINKLE | |
Name: | Andrew Byron Winkle | |
Title: | Vice President — Asset Development | |
| Fargo Acquisition Inc. | ||
By: | /s/ IRENE RUMMELHOFF | |
Name: | Irene Rummelhoff | |
Title: | President | |
[Signature Page to Joint Filing Agreement]
