| 1 | A & A Tank Truck Company | Norman, OK 73070-8969 | Oil & Gas Operator | Jul 2025 |
| 2 | Aaron Arnold B | Sulphur, OK 73086-6853 | Oil & Gas Operator | May 2004 |
| 3 | Abarr Trust (The) | Oklahoma City, OK 73179 | Oil & Gas Operator | Jul 2025 |
| 4 | Action Petroleum Service Corp | Ardmore, OK 73401 | Oil Operator | Apr 2025 |
| 5 | Adams Resources Expl. Corp. | Houston, TX 77001 | Oil & Gas Operator | Apr 2020 |
| 6 | Aexco Petroleum Inc | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 7 | Aggie Oil Company | Lakewood, CO 80226 | Oil & Gas Operator | May 2001 |
| 8 | Alexander Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 9 | Allen Oil & Gas LLC | Ardmore, OK 73401 | Oil Operator | Aug 2022 |
| 10 | Alpine Inc | Oklahoma City, OK 73134-2504 | Oil & Gas Operator | Feb 2024 |
| 11 | Altman Energy, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Oct 2025 |
| 12 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 13 | Ambrit Energy Corporation | Garland, TX 75044 | Oil & Gas Operator | Jun 2003 |
| 14 | Amerac Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2013 |
| 15 | American Natural Resources LLC | Tulsa, OK 74145-1117 | Oil & Gas Operator | May 2020 |
| 16 | American Petroleum Corp | Addison, TX 75001 | Oil & Gas Operator | Oct 2025 |
| 17 | Americo Oil Company | Oklahoma City, OK 73154 | Oil & Gas Operator | Feb 2012 |
| 18 | Anadarko Minerals Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2025 |
| 19 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jul 2025 |
| 20 | Anson Company | Oklahoma City, OK 73124 | Oil & Gas Operator | Apr 2018 |
| 21 | Antioch Disposal Well Inc | Duncan, OK 73533 | Oil Operator | Jan 1994 |
| 22 | Aog Operating LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Jun 2025 |
| 23 | Ardmore Production & Exploration Co | Ardmore, OK 73401 | Oil & Gas Operator | Jun 2025 |
| 24 | Argent Energy (Us) Holdings Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Sep 2021 |
| 25 | Aries Operating LP | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 26 | Arkoma Operations LLC | Tulsa, OK 74114-3502 | Oil & Gas Operator | Jun 2025 |
| 27 | Armor Energy II LLC | Tulsa, OK 74145 | Oil & Gas Operator | Jul 2025 |
| 28 | Arrow Energy, Incorporated | Houston, TX 77008 | Oil & Gas Operator | Jun 2025 |
| 29 | Arrow Oil & Gas, LLC | Norman, OK 73070 | Oil & Gas Operator | Oct 2025 |
| 30 | Arrow Operating Company | Dallas, TX 75231 | Oil & Gas Operator | Jun 2025 |
| 31 | Arrowhead Energy Inc | Edmond, OK 73013 | Oil & Gas Operator | Jun 2025 |
| 32 | Arvine Pipe & Supply Co Inc | Norman, OK 73069-8224 | Oil & Gas Operator | Jul 2015 |
| 33 | Atchley Resources, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Jul 2025 |
| 34 | Atlantic Richfield Company | Plano, TX 75074 | Oil & Gas Operator | Dec 2016 |
| 35 | Avalanche Oil & Gas LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Oct 2025 |
| 36 | Avalon Exploration Inc | Tulsa, OK 74119-5401 | Oil & Gas Operator | Dec 2019 |
| 37 | Aven Gas & Oil Inc | Oklahoma City, OK 73113-0491 | Oil & Gas Operator | Nov 2021 |