| 1 | A & D Exploration Company | Rockport, TX 78381 | Oil & Gas Operator | Oct 2025 |
| 2 | Adexco Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2024 |
| 3 | Adkins, R. L. Corp. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2013 |
| 4 | Aeternum Energy, LLC | Nederland, TX 77627 | Oil & Gas Operator | Oct 2025 |
| 5 | Aethon Energy Operating LLC | Dallas, TX 75251 | Oil & Gas Operator | Oct 2025 |
| 6 | American West Resources, Inc | Fort Worth, TX 76161 | Oil & Gas Operator | Oct 2025 |
| 7 | Antero Resources I, LP | Denver, CO 80202 | Oil & Gas Operator | Jun 2005 |
| 8 | Apex Operating & Equip. Co. | Bowie, TX 76230 | Oil & Gas Operator | Nov 2003 |
| 9 | Ark-La-Tex Energy, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 10 | Arp Barnett, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2018 |
| 11 | Arrington,David H. Oil & Gas,Inc | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 12 | Arrowhead Productions, LP | Fort Worth, TX 76109 | Oil & Gas Operator | Oct 2025 |
| 13 | Aruba Petroleum, Inc. | Dallas, TX 75379 | Oil & Gas Operator | Jun 2025 |
| 14 | Asher Resources | Boerne, TX 78006 | Oil & Gas Operator | May 2015 |
| 15 | Atlas Barnett, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2019 |
| 16 | Atmos Pipeline - Texas | Dallas, TX 75240 | Oil & Gas Operator | Oct 2025 |
| 17 | August Oil | Plano, TX 75093 | Oil & Gas Operator | Aug 2003 |
| 18 | Austex Energy, Inc. | Granbury, TX 76048 | Oil & Gas Operator | Apr 1993 |