| 1 | Abel, M.D. Co. | Lampasas, TX 76550 | Oil & Gas Operator | Jun 2017 |
| 2 | Ackerly Service Company, Inc. | Big Spring, TX 79721 | Oil & Gas Operator | Nov 1997 |
| 3 | Adkins, R. L. Corp. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2013 |
| 4 | Adventure Expl Partners II, LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2014 |
| 5 | Adventure Exploration PTRS, LLC | Midland, TX 79702 | Oil & Gas Operator | Aug 2012 |
| 6 | Adventure Operating Company, LLC | Midland, TX 79702 | Oil & Gas Operator | Jan 2021 |
| 7 | Aethon I LP | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 8 | Aggietech Oil, LTD. | Midland, TX 79701 | Oil & Gas Operator | Aug 2016 |
| 9 | Alleder Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2025 |
| 10 | Alpine Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 11 | Alto Minerals, Inc. | Midland, TX 79708 | Oil & Gas Operator | Apr 2019 |
| 12 | Altura Energy LTD. | Houston, TX 77210 | Oil & Gas Operator | Apr 2000 |
| 13 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 14 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 15 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 16 | American Cometra, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2008 |
| 17 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 18 | Ammonite Energy Texas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Aug 2003 |
| 19 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 20 | Amron Petroleum, Inc. | Midland, TX 79708 | Oil & Gas Operator | Jan 1996 |
| 21 | Amtex Energy, Inc. | Fort Worth, TX 76147 | Oil & Gas Operator | Jun 2025 |
| 22 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 23 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Jun 2025 |
| 24 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Apr 2025 |
| 25 | Anegada Resources | Kerrville, TX 78029 | Oil & Gas Operator | Jan 2002 |
| 26 | Angle Oil Company | Hays, KS 67601 | Oil Operator | Sep 2002 |
| 27 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Jun 2025 |
| 28 | Apv McCamey LLC | MC Camey, TX 79752 | Oil & Gas Operator | Jun 2025 |
| 29 | Arch Oil & Gas, LLC | Dallas, TX 75254 | Oil & Gas Operator | Jun 2025 |
| 30 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 31 | Arco Permian | Houston, TX 77079 | Oil & Gas Operator | Dec 2001 |
| 32 | Aries Operating, LLC | Houston, TX 77010 | Oil & Gas Operator | Feb 2010 |
| 33 | Arkland Producing Co Inc | Midland, TX 79701 | Oil & Gas Operator | Nov 2023 |
| 34 | Ashbrook Oil Co. | Big Spring, TX 79721 | Oil & Gas Operator | Apr 2020 |
| 35 | Ashland Exploration Inc | Houston, TX 77218 | Oil & Gas Operator | Nov 2000 |
| 36 | Athlon Energy Operating LLC | Denver, CO 80202 | Oil & Gas Operator | Apr 2014 |
| 37 | Athlon Fe Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2015 |
| 38 | Athlon Holdings LP | Denver, CO 80202 | Oil & Gas Operator | Jan 2015 |
| 39 | Atlantic Exploration, LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2015 |
| 40 | Atlantic Operating, Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 2015 |
| 41 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Jun 2025 |
| 42 | Atropos Exploration Company | Dallas, TX 75225 | Oil & Gas Operator | Jun 2025 |