| 1 | Abarta Oil & Gas Co., Inc. | Pittsburgh, PA 15238 | Oil & Gas Operator | Dec 2020 |
| 2 | Adkins, R. L. Corp. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2013 |
| 3 | Adventure Exploration PTRS, LLC | Midland, TX 79702 | Oil & Gas Operator | Aug 2012 |
| 4 | Adventure Operating Company, LLC | Midland, TX 79702 | Oil & Gas Operator | Jan 2021 |
| 5 | Aggietech Oil, LTD. | Midland, TX 79701 | Oil & Gas Operator | Aug 2016 |
| 6 | Aikman Oil Corp. | Oklahoma City, OK 73157 | Oil & Gas Operator | Sep 2025 |
| 7 | Alegre Energy Operating, LP | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2005 |
| 8 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2025 |
| 9 | Alpine Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 10 | Alta Energy Corporation | Midland, TX 79701 | Oil & Gas Operator | Apr 1995 |
| 11 | Altura Energy LTD. | Houston, TX 77210 | Oil & Gas Operator | Apr 2000 |
| 12 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 13 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 14 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 15 | American Energy-Perm Basin, LLC | Oklahoma City, OK 73113 | Oil & Gas Operator | May 2016 |
| 16 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 17 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 18 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 19 | Anadarko Petroleum Co | Houston, TX 77227 | Oil & Gas Operator | Feb 1998 |
| 20 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jun 2025 |
| 21 | Anegada Resources | Kerrville, TX 78029 | Oil & Gas Operator | Jan 2002 |
| 22 | Anthony, Bob G. Inc. | Brookhaven, MS 39601 | Oil & Gas Operator | Sep 2025 |
| 23 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Sep 2025 |
| 24 | Apache Energy Resources Corp | Houston, TX 77056 | Oil & Gas Operator | Mar 2015 |
| 25 | Arch Oil & Gas, LLC | Dallas, TX 75254 | Oil & Gas Operator | Sep 2025 |
| 26 | Arch Petroleum Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2008 |
| 27 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 28 | Arco Permian | Houston, TX 77079 | Oil & Gas Operator | Dec 2001 |
| 29 | Area Pipe And Equipment | Midland, TX 79702 | Oil & Gas Operator | Apr 2003 |
| 30 | Arkland Producing Co Inc | Midland, TX 79701 | Oil & Gas Operator | Nov 2023 |
| 31 | Arkland, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 1994 |
| 32 | Arnot, W. G., Jr. | Breckenridge, TX 76424 | Oil & Gas Operator | Jan 2017 |
| 33 | Athlon Fe Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2015 |
| 34 | Athlon Holdings LP | Denver, CO 80202 | Oil & Gas Operator | Jan 2015 |
| 35 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Sep 2025 |
| 36 | Avra Oil Co | Dallas, TX 75248 | Oil & Gas Operator | Sep 2025 |