| 1 | Ac Exploration, LLC | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 2 | Aethon Energy Operating LLC | Dallas, TX 75251 | Oil & Gas Operator | Oct 2025 |
| 3 | Altair Energy Corp. | Tyler, TX 75702 | Oil & Gas Operator | Jun 1994 |
| 4 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 5 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 6 | Amity Oil Co., Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 1977 |
| 7 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 8 | Amplify Energy Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 9 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 10 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 11 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jul 2025 |
| 12 | Andrew Alan Exploration, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2017 |
| 13 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 14 | Apex Royalties, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 1997 |
| 15 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 16 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 17 | Arena Resources LLC | Longview, TX 75608 | Oil & Gas Operator | Jul 2025 |
| 18 | Ark-La-Tex Energy, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 19 | Arkla Exploration Co. | Shreveport, LA 71151 | Oil & Gas Operator | Jan 1993 |
| 20 | Arlen Corporation | Houston, TX 77077 | Oil & Gas Operator | Mar 2008 |
| 21 | Arrowhead Energy Exp., LLC | Baton Rouge, LA 70816 | Oil & Gas Operator | Nov 2006 |
| 22 | Arrowhead Enterprises, Inc. | Baton Rouge, LA 70816 | Oil & Gas Operator | Apr 2001 |
| 23 | Asher Resources | Boerne, TX 78006 | Oil & Gas Operator | May 2015 |
| 24 | Atinum Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 25 | Atlantis Oil Company, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Oct 2025 |
| 26 | Atropos Exploration Company | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 27 | Austex Energy, Inc. | Granbury, TX 76048 | Oil & Gas Operator | Apr 1993 |
| 28 | Austral Oil Company Incorporated | Sulphur, LA 70663 | Oil & Gas Operator | Mar 2008 |