| 1 | A & E Minerals, LLC | Shreveport, LA 71104 | Oil & Gas Operator | Oct 2025 |
| 2 | Aber Oil & Gas Co. | Tyler, TX 75702 | Oil & Gas Operator | Nov 2013 |
| 3 | Aladdin Energy, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Feb 1999 |
| 4 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Oct 2025 |
| 5 | Alexander Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 6 | Allen Brothers Company | Oil City, LA 71061 | Oil & Gas Operator | Apr 1997 |
| 7 | Allison/Hobbs Inc. | Alba, TX 75410 | Oil & Gas Operator | Oct 2025 |
| 8 | Aln Resources Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Jan 1993 |
| 9 | Altair Energy Corp. | Tyler, TX 75702 | Oil & Gas Operator | Jun 1994 |
| 10 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 11 | American Natural Energy Corp | Oklahoma City, OK 73114 | Oil & Gas Operator | Jan 2025 |
| 12 | American Operating Company | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2003 |
| 13 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 14 | Amplify Energy Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 15 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 16 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 17 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jul 2025 |
| 18 | Andrew Alan Exploration, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2017 |
| 19 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 20 | Apex Royalties, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 1997 |
| 21 | Arbol Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Oct 2025 |
| 22 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 23 | Arena Resources LLC | Longview, TX 75608 | Oil & Gas Operator | Jul 2025 |
| 24 | Ark-La-Tex Energy Partners, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2013 |
| 25 | Ark-La-Tex Energy, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 26 | Arkla Exploration Co. | Shreveport, LA 71151 | Oil & Gas Operator | Jan 1993 |
| 27 | Arlen Corporation | Houston, TX 77077 | Oil & Gas Operator | Mar 2008 |
| 28 | Arrowhead Energy Exp., LLC | Baton Rouge, LA 70816 | Oil & Gas Operator | Nov 2006 |
| 29 | Arrowhead Enterprises, Inc. | Baton Rouge, LA 70816 | Oil & Gas Operator | Apr 2001 |
| 30 | Ascent Operating, LP | Plano, TX 75093 | Oil & Gas Operator | Aug 2008 |
| 31 | Asher Resources | Boerne, TX 78006 | Oil & Gas Operator | May 2015 |