| 1 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Apr 2024 |
| 2 | Abraxas Production Corporation | San Antonio, TX 78270 | Oil & Gas Operator | Sep 1999 |
| 3 | Acock Operating Limited | San Antonio, TX 78270 | Oil & Gas Operator | Apr 2024 |
| 4 | Acock/Anaqua Operating Co., LC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2004 |
| 5 | Acock/Anaqua Operating Co., LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2024 |
| 6 | Agp Energy Services LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |
| 7 | Alcorn Prod Co. | Victoria, TX 77902 | Oil & Gas Operator | Mar 1997 |
| 8 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Apr 2024 |
| 9 | Allegiant Resources, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Apr 2024 |
| 10 | Allegro Investments, Inc. | Victoria, TX 77903 | Oil & Gas Operator | Nov 2020 |
| 11 | Alltex Exploration, Inc. | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 12 | Alpine Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 13 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | Apr 2024 |
| 14 | Amend Energy Company | Houston, TX 77227 | Oil & Gas Operator | Apr 2002 |
| 15 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 16 | American Energy Sources, Inc. | Spring, TX 77388 | Oil & Gas Operator | Dec 2008 |
| 17 | American National Petroleum Co. | Houston, TX 77057 | Oil & Gas Operator | Aug 1995 |
| 18 | American Pumping & Trucking | New Braunfels, TX 78131 | Oil & Gas Operator | Apr 2024 |
| 19 | American Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Apr 2024 |
| 20 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 21 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 22 | Anderson Producing, Inc. | Houston, TX 77057 | Oil & Gas Operator | Sep 2013 |
| 23 | Anr Production Company | Houston, TX 77046 | Oil & Gas Operator | Aug 2017 |
| 24 | Antelope Resources Inc | Billings, MT 59101 | Oil & Gas Operator | May 2017 |
| 25 | Apache Corporation | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 26 | Araluen Energy, Inc. | Houston, TX 77094 | Oil Operator | Jun 2022 |
| 27 | Aransas DRLG & Workover Co Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Jul 2019 |
| 28 | Arcadia Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | Apr 2024 |
| 29 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 30 | Arriola Operating & Consltg Inc. | Dallas, TX 75248 | Oil Operator | Apr 2024 |
| 31 | Arrowhead Operating Inc. | Argyle, TX 76226 | Oil & Gas Operator | Apr 2024 |
| 32 | Ashland Exploration Inc | Houston, TX 77218 | Oil & Gas Operator | Nov 2000 |
| 33 | Aspect Energy, LLC | Denver, CO 80202 | Oil & Gas Operator | Apr 2024 |
| 34 | Aspect Resources LLC | Denver, CO 80202 | Oil & Gas Operator | May 2002 |
| 35 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 36 | Aurora Resources Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2024 |
| 37 | Austin Energy Operations, Inc. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Apr 2024 |
| 38 | Aviara Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2002 |
| 39 | Azimuth Energy, LLC | Denver, CO 80203 | Oil & Gas Operator | Sep 2006 |