| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | O'Hare Energy Co | Oil Operator | Dec 1983 | |
| 2 | Ogh Oil Company | Oil Operator | Sep 1995 | |
| 3 | Okmar Oil Compan | Oil & Gas Operator | Feb 1995 | |
| 4 | Opdycke Lease Partners, A General Partnership | Russell, KS 67665 | Oil Operator | Jun 2025 |
| 5 | Owen'S Pumping Service | Oil Operator | Jun 2025 | |
| 6 | Oxy USA | Oil Operator | Apr 1992 | |
| 7 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |