| 1 | A T M Corporation | Mathis, TX 78368 | Oil & Gas Operator | Oct 2002 |
| 2 | Abaco Operating, LLC | San Antonio, TX 78209 | Oil & Gas Operator | Oct 2025 |
| 3 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Oct 2025 |
| 4 | Ace Productions | Beaumont, TX 77707 | Oil & Gas Operator | Oct 2025 |
| 5 | Acock Engineering & Assoc., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jul 2002 |
| 6 | Acock Operating Limited | San Antonio, TX 78270 | Oil & Gas Operator | Oct 2025 |
| 7 | Acock/Anaqua Operating Co., LC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2004 |
| 8 | Acock/Anaqua Operating Co., LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 9 | Acoma Oil Corporation | Saint Paul, MN 55102 | Oil & Gas Operator | Oct 2025 |
| 10 | Alamo Operating Company, L. C. | San Antonio, TX 78278 | Oil & Gas Operator | Aug 2023 |
| 11 | Alcorn Prod Co. | Victoria, TX 77902 | Oil & Gas Operator | Mar 1997 |
| 12 | Aldine Oil And Gas, LP | Houston, TX 77060 | Oil & Gas Operator | Oct 2025 |
| 13 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Oct 2025 |
| 14 | Alexander Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 15 | Allegiant Resources, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Oct 2025 |
| 16 | Allegro Investments, Inc. | Victoria, TX 77903 | Oil & Gas Operator | Nov 2020 |
| 17 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | Oct 2025 |
| 18 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 19 | Ambassador Petroleum, Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2025 |
| 20 | Amend Energy Company | Houston, TX 77227 | Oil & Gas Operator | Apr 2002 |
| 21 | American Coastal Energy, Inc. | Houston, TX 77225 | Oil & Gas Operator | May 2008 |
| 22 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 23 | American Int'L Energy Corp. | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 24 | American Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Oct 2025 |
| 25 | Ampak Oil Company | Plano, TX 75074 | Oil & Gas Operator | Oct 2025 |
| 26 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 27 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jul 2025 |
| 28 | Anaqua Oil & Gas, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2008 |
| 29 | Anderson Oil LTD. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 30 | Angel Operating LLC | Metairie, LA 70033 | Oil Operator | Oct 2025 |
| 31 | Antara Resources Inc | Houston, TX 77002 | Oil & Gas Operator | Apr 2004 |
| 32 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 33 | API Operating Co. | Houston, TX 77036 | Oil & Gas Operator | Oct 2025 |
| 34 | Aquila Energy Resources Corp. | Houston, TX 77042 | Oil & Gas Operator | Nov 2013 |
| 35 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 36 | Arista Novelty, Inc. | Houston, TX 77256 | Oil & Gas Operator | Feb 1995 |
| 37 | Armour Resource Holdings, LTD. | Houston, TX 77046 | Oil & Gas Operator | Nov 1994 |
| 38 | Atapco | Houston, TX 77040 | Oil & Gas Operator | Feb 1999 |
| 39 | Atasca Resources Inc | Houston, TX 77219 | Oil & Gas Operator | Oct 2025 |
| 40 | Atinum Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 41 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 42 | Aurora Resources Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 43 | Awp Operating Company | George West, TX 78022 | Oil & Gas Operator | Oct 2025 |