| 1 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Dec 2024 |
| 2 | Acock Operating Limited | San Antonio, TX 78270 | Oil & Gas Operator | Dec 2024 |
| 3 | Acoma Oil Corporation | Saint Paul, MN 55102 | Oil & Gas Operator | Dec 2024 |
| 4 | Adobe Energy, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Nov 2004 |
| 5 | Advantage Oil & Gas, Inc. | Pinehurst, TX 77362 | Oil & Gas Operator | Dec 2024 |
| 6 | Ageron Energy, LLC | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2024 |
| 7 | Alamo Operating Company, L. C. | San Antonio, TX 78278 | Oil & Gas Operator | Aug 2023 |
| 8 | Alegre Energy Operating, LP | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2005 |
| 9 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Dec 2024 |
| 10 | Alexander, John | Pearland, TX 77588 | Oil & Gas Operator | Dec 2024 |
| 11 | Alpine Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 12 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 13 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 14 | American Coastal Energy, Inc. | Houston, TX 77225 | Oil & Gas Operator | May 2008 |
| 15 | American Cometra, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2008 |
| 16 | American Energy Op. Corp.,The | Houston, TX 77099 | Oil & Gas Operator | Dec 2024 |
| 17 | American Energy Partners Inc | Boerne, TX 78006 | Oil & Gas Operator | Dec 2011 |
| 18 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 19 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 20 | Anr Production Company | Houston, TX 77046 | Oil & Gas Operator | Aug 2017 |
| 21 | Anschutz Exploration Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2024 |
| 22 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2024 |
| 23 | Aquila Energy Resources Corp. | Houston, TX 77042 | Oil & Gas Operator | Nov 2013 |
| 24 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 25 | Arcadia Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | Dec 2024 |
| 26 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 27 | Argent Energy (Us) Holdings Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Sep 2021 |
| 28 | Aroc (Texas) Inc | Houston, TX 77090 | Oil & Gas Operator | Dec 2014 |
| 29 | Ashland Exploration Inc | Houston, TX 77218 | Oil & Gas Operator | Nov 2000 |
| 30 | Aspect Energy, LLC | Denver, CO 80202 | Oil & Gas Operator | Dec 2024 |
| 31 | Aspect Resources LLC | Denver, CO 80202 | Oil & Gas Operator | May 2002 |
| 32 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2024 |
| 33 | Axis Energy Corporation | Roswell, NM 88202 | Oil & Gas Operator | Dec 2024 |
| 34 | Azimuth Energy, LLC | Denver, CO 80203 | Oil & Gas Operator | Sep 2006 |