| 1 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Dec 2024 |
| 2 | Abraxas Production Corporation | San Antonio, TX 78270 | Oil & Gas Operator | Sep 1999 |
| 3 | Adams Branch Exploration Company | Abilene, TX 79608 | Oil & Gas Operator | Jul 2002 |
| 4 | Adkins, R. L. Corp. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2013 |
| 5 | Alegre Energy Operating, LP | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2005 |
| 6 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Dec 2024 |
| 7 | Alexander Resources, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Dec 2024 |
| 8 | Allegro Investments, Inc. | Victoria, TX 77903 | Oil & Gas Operator | Nov 2020 |
| 9 | Alpha Energy | Anson, TX 79501 | Oil & Gas Operator | Oct 2016 |
| 10 | Alpine Petroleum | Abilene, TX 79608 | Oil & Gas Operator | Jul 2018 |
| 11 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 12 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 13 | Anathema, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Dec 1994 |
| 14 | Anderson, Carl T. | Wichita Falls, TX 76301 | Oil & Gas Operator | Feb 2014 |
| 15 | Anderson, Dorman | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2012 |
| 16 | Anderson, James K. Inc. | Abilene, TX 79608 | Oil & Gas Operator | Dec 2024 |
| 17 | Antle, E. | Graham, TX 76450 | Oil & Gas Operator | Oct 1994 |
| 18 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2024 |
| 19 | Arbol Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Dec 2024 |
| 20 | Arch Petroleum Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2008 |
| 21 | Arrowhead Operating Inc. | Argyle, TX 76226 | Oil & Gas Operator | Dec 2024 |
| 22 | Ashland Exploration Inc | Houston, TX 77218 | Oil & Gas Operator | Nov 2000 |
| 23 | Ashtola Exploration Company,Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Dec 2024 |
| 24 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2024 |
| 25 | Aurora Power Resources, Inc. | Houston, TX 77042 | Oil & Gas Operator | Aug 2018 |