| 1 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 2 | Atlas Barnett, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2019 |
| 3 | BKV North Texas, LLC | Fort Worth, TX 76106 | Oil & Gas Operator | May 2025 |
| 4 | Blue River Inc. | Abilene, TX 79608 | Oil Operator | May 2025 |
| 5 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | May 2025 |
| 6 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 2025 |
| 7 | Cumming Company, Inc. The | Fort Worth, TX 76116 | Oil & Gas Operator | May 2025 |
| 8 | Eagleridge Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | May 2025 |
| 9 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | May 2025 |
| 10 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 11 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 12 | Harding Company | Dallas, TX 75244 | Oil & Gas Operator | Jan 2015 |
| 13 | K & K Oil Co. | Corsicana, TX 75109 | Oil & Gas Operator | May 2025 |
| 14 | Kathler Oil Interests | Frisco, TX 75034 | Oil & Gas Operator | May 2025 |
| 15 | Legend Natural Gas IV, LP | Houston, TX 77094 | Oil & Gas Operator | Feb 2015 |
| 16 | Means Oil Company, LLC | Corsicana, TX 75110 | Oil & Gas Operator | May 2025 |
| 17 | Metroplex Barnett Shale LLC | Houston, TX 77001 | Gas Operator | Sep 2008 |
| 18 | Mixon, Robert N. | Lometa, TX 76853 | Oil & Gas Operator | May 2025 |
| 19 | Plains Production Inc | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 1995 |
| 20 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 21 | Rio-Tex, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | May 2025 |
| 22 | Rosewood Resources, Inc. | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 23 | Sage Natural Resources LLC | Tulsa, OK 74170 | Oil & Gas Operator | May 2025 |
| 24 | Seismic Leasing Service | Denver, CO 80216 | Oil & Gas Operator | Aug 2000 |
| 25 | Skewes Operating Company | Bluefield, VA 24605 | Oil & Gas Operator | May 2025 |
| 26 | Spartan Oil Corporation | Abilene, TX 79601 | Oil & Gas Operator | Aug 2003 |
| 27 | Stacha, Eddy A. | Rice, TX 75155 | Oil & Gas Operator | May 2025 |
| 28 | Summitt Resources | Corsicana, TX 75110 | Oil & Gas Operator | Apr 2008 |
| 29 | Tep Barnett USA, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 30 | Titan Operating, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2012 |
| 31 | TK Drilling Corp. | Tulsa, OK 74133 | Oil & Gas Operator | Feb 2025 |
| 32 | Trans-Texas Energy Group LLC | Mineral Wells, TX 76068 | Oil & Gas Operator | Jul 2015 |
| 33 | Trinity River Energy Oper, LLC | Houston, TX 77008 | Oil & Gas Operator | May 2018 |
| 34 | Triton Energy LLC | Wortham, TX 76693 | Oil & Gas Operator | May 2025 |
| 35 | Trust Oil Co. | Pine, CO 80470 | Oil & Gas Operator | May 2025 |
| 36 | Txu Lone Star Pipeline | Dallas, TX 75201 | Oil & Gas Operator | Oct 2003 |
| 37 | Upp Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 38 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | May 2025 |