| 1 | Americo Energy Resources, LLC | Houston, TX 77063 | Oil & Gas Operator | Oct 2025 |
| 2 | Arrowhead Operating Inc. | Argyle, TX 76226 | Oil & Gas Operator | Oct 2025 |
| 3 | Blackwell Operating Company | Houston, TX 77227 | Oil & Gas Operator | Jun 2007 |
| 4 | Brahman Operating LLC | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 5 | Bridwell Oil Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 6 | Cox, Robert G. & Associates,Inc. | Dallas, TX 75225 | Oil & Gas Operator | Feb 1994 |
| 7 | Cumming Company, Inc. The | Fort Worth, TX 76116 | Oil & Gas Operator | Oct 2025 |
| 8 | Dart Oil & Gas Corporation | Mason, MI 48854 | Oil & Gas Operator | Jun 2018 |
| 9 | Del Petroleum Corporation | Dallas, TX 75219 | Oil & Gas Operator | Jan 2012 |
| 10 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Oct 2025 |
| 11 | Echo Production Inc | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 12 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 13 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 14 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jun 2025 |
| 15 | Exit Oil & Gas | Flower Mound, TX 75028 | Oil & Gas Operator | Oct 2025 |
| 16 | Foundation Energy Management, LLC | Addison, TX 75001 | Oil & Gas Operator | Oct 2025 |
| 17 | Four Sevens Operating Co., LTD. | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 18 | Johnson & Ernst Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Sep 2018 |
| 19 | Kimbell Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 20 | Lone Star Gas Co. | Dallas, TX 75201 | Oil & Gas Operator | Jul 1999 |
| 21 | Louisiana Land & Exploration Co. | Houston, TX 77210 | Oil & Gas Operator | Sep 2013 |
| 22 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Aug 2025 |
| 23 | Morris, W. Dale Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | Oct 2025 |
| 24 | Patton, E. N. Oil Company, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 25 | Quicksilver Resources Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2018 |
| 26 | Regency Petroleum Co. | Irving, TX 75016 | Oil & Gas Operator | Aug 2002 |
| 27 | Sedona Oil & Gas Corporation | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 28 | STB Energy Inc. | Tulsa, OK 74105 | Oil & Gas Operator | Jul 2008 |
| 29 | Subsurface Energy Corp. | Coleman, TX 76834 | Oil & Gas Operator | Oct 2025 |
| 30 | Tex-Ann Oil & Gas Services, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Oct 2025 |
| 31 | West Bay Exploration Company | Muenster, TX 76252 | Oil & Gas Operator | Jul 2025 |