| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | A. J. Hayes | Oil & Gas Operator | Dec 1998 | |
| 2 | A.L.S. Resources Inc. | Oil Operator | Dec 2004 | |
| 3 | Aba Energy Corporation | Oil & Gas Operator | Oct 2025 | |
| 4 | Aera Energy LLC | Oil & Gas Operator | Oct 2025 | |
| 5 | Alanmar Energy | Gas Operator | Jan 2018 | |
| 6 | Allied Western Petroleum | Oil & Gas Operator | Sep 2025 | |
| 7 | Almond Crest Oil LLC | Oil & Gas Operator | Sep 2025 | |
| 8 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 9 | Amrich Energy Inc. | Oil & Gas Operator | Sep 2025 | |
| 10 | Anacapa Oil Corporation | Gas Operator | Sep 2025 | |
| 11 | Anadime Energy Services Inc. | Oil & Gas Operator | Dec 2009 | |
| 12 | Ancora-Verde Corporation | Oil & Gas Operator | Dec 2004 | |
| 13 | Andrew L. Newkirk | Oil Operator | Sep 2025 | |
| 14 | Angus Petroleum Corporation | Chicago, IL 60660 | Oil & Gas Operator | Dec 2022 |
| 15 | Ann Marie Tiers | Oil Operator | Dec 1996 | |
| 16 | Anterra Services Inc. | Oil & Gas Operator | Oct 2025 | |
| 17 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2025 |
| 18 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 19 | Arco Western Energy Co. | Oil & Gas Operator | Dec 1999 | |
| 20 | Argo Petroleum Corporation | Oil & Gas Operator | Dec 1989 | |
| 21 | Armca Oil & Gas LLC | Oil Operator | Sep 2025 | |
| 22 | Armstrong Petroleum Corporation | Oil & Gas Operator | Sep 2025 | |
| 23 | Arthur McAdams | Oil & Gas Operator | Sep 2025 | |
| 24 | Ashe Road Properties L.P. | Oil & Gas Operator | Dec 2009 | |
| 25 | Aspen Exploration Corporation | Oil & Gas Operator | Dec 2007 | |
| 26 | Atlantic Oil Company | Oil & Gas Operator | Sep 2025 | |
| 27 | Atlantic Richfield Company | Plano, TX 75074 | Oil & Gas Operator | Dec 2016 |
| 28 | Austin Oil Company | Oil & Gas Operator | Dec 2000 |