| 1 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | May 2024 |
| 2 | Aikman Brothers LLC | Amarillo, TX 79109 | Oil & Gas Operator | Jan 2024 |
| 3 | Aikman Oil Corp. | Oklahoma City, OK 73157 | Oil & Gas Operator | May 2024 |
| 4 | Aladdin Petroleum Corporation | Wichita, KS 67202 | Oil & Gas Operator | Jan 2021 |
| 5 | Alegre Energy Operating, LP | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2005 |
| 6 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | May 2024 |
| 7 | Alexander Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 8 | Alpar Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jul 2011 |
| 9 | Amarillo Exploration, Inc. | Dallas, TX 75360 | Oil & Gas Operator | May 2024 |
| 10 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 11 | Amedan Resources, Inc. | Chickasha, OK 73023 | Oil & Gas Operator | Mar 2008 |
| 12 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 13 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 14 | Anadarko Minerals Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2024 |
| 15 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jan 2024 |
| 16 | Ananda Energy Inc. | Pampa, TX 79065 | Oil & Gas Operator | Jan 2021 |
| 17 | Anderman/Smith Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Sep 1995 |
| 18 | Anson Company | Oklahoma City, OK 73124 | Oil & Gas Operator | Apr 2018 |
| 19 | Apache Corporation | Houston, TX 77056 | Oil & Gas Operator | May 2024 |
| 20 | Aquila Energy Resources Corp. | Houston, TX 77042 | Oil & Gas Operator | Nov 2013 |
| 21 | Arnold Oil Properties LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | May 2024 |
| 22 | Arnold Oil Properties, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | May 2019 |
| 23 | Arrington CJM, Inc. | Canadian, TX 79014 | Oil & Gas Operator | Nov 2021 |
| 24 | Arrowhead Resources, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2024 |
| 25 | Asher Resources | Boerne, TX 78006 | Oil & Gas Operator | May 2015 |
| 26 | Athena Energy, Inc. | Gallatin, TN 37066 | Oil & Gas Operator | May 2024 |
| 27 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | May 2024 |
| 28 | Axis Energy Corporation | Roswell, NM 88202 | Oil & Gas Operator | May 2024 |