| 1 | A & A Tank Truck Company | Norman, OK 73070-8969 | Oil & Gas Operator | Feb 2026 |
| 2 | Abundance Energy I LLC | Tulsa, OK 74114 | Gas Operator | Jan 2026 |
| 3 | Abundance Energy Services LLC | Tulsa, OK 74114 | Gas Operator | Jan 2026 |
| 4 | Agave Energy Inc | Stigler, OK 74462 | Oil & Gas Operator | Jan 2026 |
| 5 | Alexander Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 6 | Alexander Oil Company | Loco, OK 73442-9409 | Oil & Gas Operator | Dec 2025 |
| 7 | Amax Oil & Gas Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 8 | An-Son Corp | Oklahoma City, OK 73124 | Oil & Gas Operator | Jan 2006 |
| 9 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Apr 2026 |
| 10 | Anadarko Minerals Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2026 |
| 11 | Anc Investments LLC | Enid, OK 73701-1823 | Gas Operator | Jan 2026 |
| 12 | Antara Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 2004 |
| 13 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Apr 2026 |
| 14 | Arkla Energy Resources | Shreveport, LA 71151 | Oil & Gas Operator | Mar 2015 |
| 15 | Arkoma Holding Corporation | Oklahoma City, OK 73102-5684 | Gas Operator | Jul 2007 |
| 16 | Arkoma Operations LLC | Tulsa, OK 74114-3502 | Oil & Gas Operator | Jan 2026 |
| 17 | Arkoma Production Company | Shreveport, LA 71101 | Gas Operator | Apr 2020 |
| 18 | Arkoma Resources LLC | Henryetta, OK 74437 | Oil & Gas Operator | Feb 2026 |
| 19 | Arrow Oil & Gas, LLC | Norman, OK 73070 | Oil & Gas Operator | Apr 2026 |
| 20 | Atlantic Richfield Company | Houston, TX 77079 | Oil & Gas Operator | Dec 2016 |
| 21 | Atls Production Company LLC | Fort Worth, TX 76102-7426 | Gas Operator | Sep 2020 |