| 1 | T-N-T Engineering, Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Dec 2025 |
| 2 | Tahoe Exploration Inc. | Abilene, TX 79608 | Oil & Gas Operator | Mar 2016 |
| 3 | Talon Production, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Dec 2025 |
| 4 | Taurus Exploration U.S.A., Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 1998 |
| 5 | Taylor, Ben J. Inc. | Fort Worth, TX 76185 | Oil & Gas Operator | Feb 2022 |
| 6 | Taylor-McIlhenny Oper. Co., Inc. | Lewisville, TX 75029 | Oil & Gas Operator | Jan 1996 |
| 7 | TCS Petroleum Co., LLC | Abilene, TX 79608 | Oil & Gas Operator | Dec 2025 |
| 8 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 9 | Telesis Operating Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Dec 2025 |
| 10 | Tema Oil And Gas Company | Houston, TX 77084 | Oil & Gas Operator | Dec 2025 |
| 11 | Tema Oil And Gas, LLC | Houston, TX 77040 | Oil & Gas Operator | Apr 2000 |
| 12 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Dec 2025 |
| 13 | Texaco Exploration & Prod | Midland, TX 79702 | Oil & Gas Operator | Aug 2002 |
| 14 | Texakoma E & P, LLC | Plano, TX 75024 | Oil & Gas Operator | Dec 2025 |
| 15 | Texakoma Oil & Gas Corp | Dallas, TX 75240 | Oil & Gas Operator | Sep 2014 |
| 16 | Texas Crude Operator, Inc. | Houston, TX 77098 | Oil & Gas Operator | Aug 2017 |
| 17 | Texas United Geoproduction, Inc. | Abilene, TX 79606 | Oil & Gas Operator | Dec 2025 |
| 18 | Texland Petroleum Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2003 |
| 19 | Texona Petroleum Corporation | Houston, TX 77084 | Oil & Gas Operator | Aug 2003 |
| 20 | Texstar North America, Inc. | Waynesboro, MS 39367 | Oil & Gas Operator | Aug 1994 |
| 21 | Texzona Oil & Gas, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Dec 1997 |
| 22 | Three Rivers Operating Co LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 23 | Tidmore, Ann | Albany, TX 76430 | Oil & Gas Operator | Dec 2025 |
| 24 | Titan Energy, Inc. | Austin, TX 78703 | Oil & Gas Operator | Dec 2025 |
| 25 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Dec 2025 |
| 26 | Toreador Exploration & Prod Inc | Dallas, TX 75240 | Oil & Gas Operator | Feb 2008 |
| 27 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Dec 2025 |
| 28 | Trey Exploration, Inc. | San Angelo, TX 76901 | Oil & Gas Operator | Dec 2020 |
| 29 | Tri-Tex Exploration LTD | Abilene, TX 79608 | Oil Operator | Apr 2019 |
| 30 | Triangle P Development Corp. | Bronte, TX 76933 | Oil & Gas Operator | Dec 2025 |
| 31 | Trilogy Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Dec 2025 |
| 32 | Triple T Resources, LP | Dallas, TX 75205 | Oil & Gas Operator | Jun 2025 |
| 33 | Tripower Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2020 |
| 34 | Triton Operating LLC | Wichita Falls, TX 76310 | Oil & Gas Operator | Dec 2025 |
| 35 | Tucker Drilling Company, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Jul 1996 |
| 36 | Tuthill & Barbee | Amarillo, TX 79101 | Oil & Gas Operator | Nov 1994 |