| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | O'Neal Oil & Gas Co | Fort Worth, TX 76107-1479 | Oil & Gas Operator | Feb 2024 |
| 2 | Oak Resources Inc | Tulsa, OK 74153 | Oil & Gas Operator | Aug 2013 |
| 3 | Oklahoma Liquid Resources Inc | Owasso, OK 74055-0841 | Oil & Gas Operator | Jan 2024 |
| 4 | Oklahoma Oil Tactics Inc | Edmond, OK 73003-1351 | Oil & Gas Operator | Mar 2015 |
| 5 | Oklahoma Petroleum Allies LLC | Ardmore, OK 73401 | Oil Operator | Oct 2023 |
| 6 | Oneok Resources Company | Tulsa, OK 74102 | Oil & Gas Operator | Feb 2017 |
| 7 | Oryx Crude Trading & Transporation LP | Dallas, TX 75221 | Oil & Gas Operator | Jun 1999 |