| 1 | A.D. Operating | Graham, TX 76450 | Oil & Gas Operator | Apr 2026 |
| 2 | A.E.N. Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Jan 1996 |
| 3 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Apr 2026 |
| 4 | Acock/Anaqua Operating Co., LP | Corpus Christ, TX 78401 | Oil & Gas Operator | Apr 2026 |
| 5 | Acoma Oil Corporation | Saint Paul, MN 55102 | Oil & Gas Operator | Apr 2026 |
| 6 | Adkins, R. L. Corp. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2013 |
| 7 | Aethon I LP | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 8 | Alaron Energy, Inc. | Irving, TX 75038 | Oil & Gas Operator | Apr 2026 |
| 9 | Alda Oil & Gas Corporation | Nichols Hill, OK 73116 | Oil & Gas Operator | Jan 2004 |
| 10 | Alegre Energy Operating, LP | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2005 |
| 11 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Apr 2026 |
| 12 | Alexander Resources, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Apr 2026 |
| 13 | Allegro Operating, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Apr 2026 |
| 14 | Alpha Exploration Co. | Wichita Falls, TX 76309 | Oil & Gas Operator | Oct 1998 |
| 15 | Alumni Oil LLC | Plano, TX 75024 | Oil Operator | Apr 2026 |
| 16 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 17 | Amerac Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2013 |
| 18 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 19 | American Cascade Energy, Inc. | Barker, TX 77413 | Oil & Gas Operator | Apr 2026 |
| 20 | American Cometra, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2008 |
| 21 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 22 | Amoco Production Company | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 23 | Ampak Oil Company | Plano, TX 75074 | Oil & Gas Operator | Apr 2026 |
| 24 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Feb 2026 |
| 25 | Anathema, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Dec 1994 |
| 26 | Andalucia Oil Company | San Antonio, TX 78258 | Oil Operator | Apr 2026 |
| 27 | Anderson, James K. Inc. | Abilene, TX 79608 | Oil & Gas Operator | Apr 2026 |
| 28 | Antle Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Apr 2026 |
| 29 | Apex Royalties, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 1997 |
| 30 | Arabella Petroleum Company, LLC | Austin, TX 78701 | Oil & Gas Operator | Apr 2026 |
| 31 | Arcadian Resources LLC | Glen Elder, KS 67446 | Oil & Gas Operator | Apr 2026 |
| 32 | Aspen Exploration, Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2012 |
| 33 | Atapco | Houston, TX 77040 | Oil & Gas Operator | Feb 1999 |
| 34 | Atasca Resources, Inc. | Houston, TX 77219 | Oil & Gas Operator | Apr 2026 |
| 35 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2026 |
| 36 | Atmos Pipeline - Texas | Dallas, TX 75240 | Oil & Gas Operator | Apr 2026 |
| 37 | Atropos Exploration Company | Dallas, TX 75225 | Oil & Gas Operator | Apr 2026 |
| 38 | Avad Operating, LLC | Dallas, TX 75201 | Oil & Gas Operator | Apr 2026 |
| 39 | Avery, Irving W. | Buena VIsta, CO 81211 | Oil & Gas Operator | Mar 2008 |
| 40 | Axis Energy Corporation | Roswell, NM 88202 | Oil & Gas Operator | Apr 2026 |