| 1 | A T M Corporation | Mathis, TX 78368 | Oil & Gas Operator | Oct 2002 |
| 2 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Oct 2025 |
| 3 | Abraxas Production Corporation | San Antonio, TX 78270 | Oil & Gas Operator | Sep 1999 |
| 4 | Ac Exploration, LLC | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 5 | Acock Engineering & Assoc., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jul 2002 |
| 6 | Acock/Anaqua Operating Co., LC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2004 |
| 7 | Acock/Anaqua Operating Co., LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 8 | Advantage Oil & Gas, Inc. | Pinehurst, TX 77362 | Oil & Gas Operator | Oct 2025 |
| 9 | Alamo Operating Company, L. C. | San Antonio, TX 78278 | Oil & Gas Operator | Aug 2023 |
| 10 | Albrecht, Phil A., Jr. | Victoria, TX 77901 | Oil & Gas Operator | Jun 2005 |
| 11 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Oct 2025 |
| 12 | Allegro Investments, Inc. | Victoria, TX 77903 | Oil & Gas Operator | Nov 2020 |
| 13 | Amend Energy Company | Houston, TX 77227 | Oil & Gas Operator | Apr 2002 |
| 14 | Amerac Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2013 |
| 15 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 16 | American Int'L Energy Corp. | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 17 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 18 | Ampak Oil Company | Plano, TX 75074 | Oil & Gas Operator | Oct 2025 |
| 19 | Anaqua Oil & Gas, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2008 |
| 20 | Anderson Oil LTD. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 21 | Anderson Producing, Inc. | Houston, TX 77057 | Oil & Gas Operator | Sep 2013 |
| 22 | Apex Energy, Inc. | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Oct 2025 |
| 23 | Aransas DRLG & Workover Co Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Jul 2019 |
| 24 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 25 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 26 | Aries Operating, LLC | Houston, TX 77010 | Oil & Gas Operator | Feb 2010 |
| 27 | Aroc (Texas) Inc | Houston, TX 77090 | Oil & Gas Operator | Dec 2014 |
| 28 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 29 | August Oil | Plano, TX 75093 | Oil & Gas Operator | Aug 2003 |
| 30 | Aurora Resources Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |