| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | U.S. Energy Development Corp | Arlington, TX 76011 | Oil & Gas Operator | Apr 2024 |
| 2 | Ultramar Oil & Gas LTD | Houston, TX 77060 | Oil & Gas Operator | Jul 1995 |
| 3 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 4 | Underwood Oil And Gas LLC | Oil & Gas Operator | Feb 2024 | |
| 5 | Union Texas Petroleum Corp. | Houston, TX 77252-2120 | Oil & Gas Operator | Dec 2014 |
| 6 | Union Valley Petroleum Corporation | Enid, OK 73701 | Oil & Gas Operator | Feb 2024 |
| 7 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2024 |
| 8 | United Oil Corporation | Denver, CO 80202-3813 | Oil & Gas Operator | Jan 2024 |
| 9 | United Production Company LLC | Edmond, OK 73083-5348 | Oil & Gas Operator | Feb 2024 |
| 10 | Usedc Okc LLC | Oil & Gas Operator | May 2018 |