| 1 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 2 | American Exploration Oper. Co. | | Oil & Gas Operator | May 1990 |
| 3 | Cardinal Operating Corporation | Waxahachie, TX 75165 | Oil & Gas Operator | Jan 1997 |
| 4 | Chisos, LTD | Houston, TX 77098 | Oil & Gas Operator | Apr 2024 |
| 5 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 6 | Duer Wagner & Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 1998 |
| 7 | Exchange Oil & Gas Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1987 |
| 8 | Exoro Energy, L.L.C. | | Oil & Gas Operator | Jun 2021 |
| 9 | Florida Gas Transmission Co. | | Oil Operator | Dec 2007 |
| 10 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2010 |
| 11 | Koch Gateway Pipeline Company | | Oil & Gas Operator | Feb 2001 |
| 12 | La. Land & Expl. Co. | | Oil & Gas Operator | Dec 2010 |
| 13 | Lagniappe Operating, LLC | | Oil Operator | Dec 2023 |
| 14 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 15 | Mosbacher Energy Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2024 |
| 16 | Ocean Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 17 | Oracle Oil, LLC | | Oil & Gas Operator | Jul 2013 |
| 18 | Paloma Natural Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2023 |
| 19 | Petro-Ventures, Inc. - Miss. | | Oil & Gas Operator | Apr 2009 |
| 20 | Pompano Resource Operator LLC | | Oil & Gas Operator | Jan 2024 |
| 21 | PV Of MS Inc | | Oil & Gas Operator | Jan 2019 |
| 22 | R. W. Tyson Producing Co.,Inc | | Oil & Gas Operator | Feb 2024 |
| 23 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 24 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 25 | Seneca Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 26 | Skrivanos Engineering, Inc. | Shreveport, LA 71164 | Oil & Gas Operator | Dec 2011 |
| 27 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 28 | Southern Natural Gas Co | Houston, TX 77001 | Oil & Gas Operator | Dec 2011 |
| 29 | Southern Natural Gas Company LLC | | Oil & Gas Operator | Nov 2023 |
| 30 | TMR Exploration, Inc. | Bossier City, LA 71171 | Oil & Gas Operator | Apr 2024 |
| 31 | TXP Operating Company | | Oil & Gas Operator | Jul 1992 |
| 32 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 33 | United Gas Pipe Line Co. | | Oil Operator | Aug 1993 |
| 34 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Apr 2024 |