| 1 | Abundance Energy I LLC | Tulsa, OK 74114 | Gas Operator | Feb 2026 |
| 2 | Abundance Energy Services LLC | Tulsa, OK 74114 | Gas Operator | Feb 2026 |
| 3 | Alda Oil & Gas Corporation | Nichols Hill, OK 73116 | Oil & Gas Operator | Jan 2004 |
| 4 | Alpine Inc | Oklahoma City, OK 73134-2504 | Oil & Gas Operator | Feb 2024 |
| 5 | American Natural Energy Corp | Oklahoma City, OK 73114 | Oil & Gas Operator | Jan 2025 |
| 6 | Anc Investments LLC | Enid, OK 73701-1823 | Gas Operator | Feb 2026 |
| 7 | Ardmore Production & Exploration Co | Ardmore, OK 73401 | Oil & Gas Operator | Feb 2026 |
| 8 | Arkana Operating Company Inc | Fort Worth, TX 76116-5707 | Oil & Gas Operator | Jul 2008 |
| 9 | Arkoma Operations LLC | Tulsa, OK 74114-3502 | Oil & Gas Operator | Feb 2026 |
| 10 | Arkoma Resources LLC | Henryetta, OK 74437 | Oil & Gas Operator | Mar 2026 |
| 11 | Arrow Oil & Gas, LLC | Norman, OK 73070 | Oil & Gas Operator | Jun 2026 |
| 12 | Aruba Petroleum, Inc. | Dallas, TX 75379 | Oil & Gas Operator | Feb 2026 |
| 13 | Aspen Land & Exploration Co | Tulsa, OK 74159-0335 | Oil & Gas Operator | Jul 2001 |
| 14 | Athabasca Energy Corporation | Simonton, TX 77476 | Oil & Gas Operator | Dec 2017 |