| 1 | Aber Oil & Gas Co. | Tyler, TX 75702 | Oil & Gas Operator | Nov 2013 |
| 2 | Ableready, Inc. | Houston, TX 77269 | Oil & Gas Operator | Jun 2026 |
| 3 | Adexco Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2024 |
| 4 | Adkins, R. L. Corp. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2013 |
| 5 | Aeternum Energy, LLC | Tyler, TX 75713 | Oil & Gas Operator | Jun 2026 |
| 6 | Alaron Energy, Inc. | Irving, TX 75038 | Oil & Gas Operator | Jun 2026 |
| 7 | Albert, David Oil & Gas | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 8 | Alleder Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 9 | Allison/Hobbs Inc. | Alba, TX 75410 | Oil & Gas Operator | Jun 2026 |
| 10 | Altex Resources, Inc. | Carney, OK 74832 | Oil & Gas Operator | Mar 2015 |
| 11 | Amen Oil LLC | Graham, TX 76450 | Oil & Gas Operator | Jun 2026 |
| 12 | American Star Energy & Min. Corp | Katy, TX 77449 | Oil & Gas Operator | Jun 2026 |
| 13 | American West Resources, Inc | Fort Worth, TX 76161 | Oil & Gas Operator | Jun 2026 |
| 14 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Mar 2026 |
| 15 | Antero Resources I, LP | Denver, CO 80202 | Oil & Gas Operator | Jun 2005 |
| 16 | Antle Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Jun 2026 |
| 17 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 18 | Arco Oil & Gas Co.-Silsbee | Lafayette, LA 70505 | Oil & Gas Operator | Jul 1993 |
| 19 | Arledge & Young, Inc. | Weatherford, TX 76086 | Oil & Gas Operator | Feb 1999 |
| 20 | Arrington Oil&Gas Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 21 | Arrington,David H. Oil & Gas,Inc | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 22 | Arrowhead Productions, LP | Fort Worth, TX 76109 | Oil & Gas Operator | Jun 2026 |
| 23 | Aruba Petroleum, Inc. | Dallas, TX 75379 | Oil & Gas Operator | Feb 2026 |
| 24 | Aspect Energy, LLC | Denver, CO 80202 | Oil & Gas Operator | Jun 2026 |
| 25 | Athena Resources, Inc. | Dallas, TX 75248 | Oil & Gas Operator | Jun 2026 |
| 26 | Atlas Barnett, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2019 |
| 27 | Atmos Pipeline - Texas | Dallas, TX 75240 | Oil & Gas Operator | Jun 2026 |
| 28 | Atoka Energy LLC | Gainesville, TX 76241 | Oil & Gas Operator | Jun 2026 |
| 29 | Atoka Operating, Inc. | Gainesville, TX 76241 | Oil & Gas Operator | Jun 2026 |
| 30 | Ausanka Oil Operations | Wichita Falls, TX 76308 | Oil & Gas Operator | Jun 1995 |
| 31 | Austex Energy, Inc. | Granbury, TX 76048 | Oil & Gas Operator | Apr 1993 |
| 32 | Austin Energy Operations, Inc. | Corpus Christ, TX 78410 | Oil & Gas Operator | Jun 2026 |