| 1 | A. J. Hodges, Ind. Inc Et Al | | Oil & Gas Operator | Jan 1979 |
| 2 | Addison Oil, LLC | Addison, TX 75001 | Oil & Gas Operator | Mar 2013 |
| 3 | Aldridge Operating Co., LLC | | Oil & Gas Operator | Aug 2019 |
| 4 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 5 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 6 | BPR Energy, Inc. | | Oil & Gas Operator | Apr 2021 |
| 7 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Jun 2025 |
| 8 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Oct 2025 |
| 9 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 10 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 11 | Goldking Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 12 | Indigo II Louisiana Operating LLC | | Oil & Gas Operator | Feb 2015 |
| 13 | Indigo Minerals LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2022 |
| 14 | Lamar Hunt | | Oil & Gas Operator | Oct 2003 |
| 15 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Oct 2025 |
| 16 | Perdido Energy Louisiana, LLC | | Oil & Gas Operator | Dec 2024 |
| 17 | Pie La Operating, LLC | | Oil & Gas Operator | Jan 2025 |
| 18 | Pilot Resources, Inc. | | Oil & Gas Operator | May 2013 |
| 19 | Planet Resource Operating, LLC | | Oil & Gas Operator | Nov 2024 |
| 20 | Prime Rock Resources La LLC | | Oil & Gas Operator | Dec 2024 |
| 21 | Rme Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Nov 2016 |
| 22 | Sohio Petroleum Co. Et Al | | Oil & Gas Operator | May 1979 |
| 23 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 24 | Sonoran Energy Inc. | Addison, TX 75001 | Oil & Gas Operator | Oct 2025 |
| 25 | SV Energy Company, LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2017 |
| 26 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 27 | Swift Energy Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2017 |
| 28 | Tennessee Gas Pipeline Company | | Oil & Gas Operator | Dec 2011 |
| 29 | Texegy Operating Company LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 30 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 31 | Yuma E & P Company, Inc. | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 32 | Zarvona Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |