| 1 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Dec 2024 |
| 2 | Acock Engineering & Assoc., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jul 2002 |
| 3 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Dec 2024 |
| 4 | Allegro Investments, Inc. | Victoria, TX 77903 | Oil & Gas Operator | Nov 2020 |
| 5 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | Dec 2024 |
| 6 | Alyana Energy Corporation | Houston, TX 77227 | Oil & Gas Operator | Apr 1995 |
| 7 | Alyndson Oil & Gas Inc. | Alice, TX 78333 | Oil & Gas Operator | Jun 2000 |
| 8 | Ambassador Petroleum, Inc. | Katy, TX 77494 | Oil & Gas Operator | Dec 2024 |
| 9 | American Energy Partners Inc | Boerne, TX 78006 | Oil & Gas Operator | Dec 2011 |
| 10 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 11 | American Int'L Energy Corp. | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 12 | American Pumping & Trucking | New Braunfels, TX 78131 | Oil & Gas Operator | Dec 2024 |
| 13 | Ammonite Energy Texas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Aug 2003 |
| 14 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Sep 2024 |
| 15 | Anderson Oil LTD. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 16 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2024 |
| 17 | Aransas DRLG & Workover Co Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Jul 2019 |
| 18 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 19 | Argent Energy (Us) Holdings Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Sep 2021 |
| 20 | Ariel Resources, Inc. | Dallas, TX 75287 | Oil & Gas Operator | May 1997 |
| 21 | Arkla Exploration Co. | Shreveport, LA 71151 | Oil & Gas Operator | Jan 1993 |
| 22 | Armour Resource Holdings, LTD. | Houston, TX 77046 | Oil & Gas Operator | Nov 1994 |
| 23 | Ashland Exploration Inc | Houston, TX 77218 | Oil & Gas Operator | Nov 2000 |
| 24 | Atapco | Houston, TX 77040 | Oil & Gas Operator | Feb 1999 |
| 25 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2024 |
| 26 | Atoka Operating, Inc. | Gainesville, TX 76241 | Oil & Gas Operator | Dec 2024 |
| 27 | Auburn Enterprises, Inc. | Kyle, TX 78640 | Oil & Gas Operator | Aug 2003 |
| 28 | Aurora Resources Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 29 | Aviara Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2002 |