| 1 | T.O.I. | Midland, TX 79710 | Oil & Gas Operator | Mar 2001 |
| 2 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Feb 2026 |
| 3 | Tamarack Petroleum Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Feb 2026 |
| 4 | Targa Midstream Services LLC | Houston, TX 77002 | Oil Operator | Mar 2023 |
| 5 | Taurus Exploration U.S.A., Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 1998 |
| 6 | Taurus Minerals, Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |
| 7 | Taurus Operating, Inc. | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 8 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Feb 2026 |
| 9 | Tejas Permian Operating, LLC | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |
| 10 | Telesis Operating Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Feb 2026 |
| 11 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Feb 2026 |
| 12 | Texas Crude Operator, Inc. | Houston, TX 77098 | Oil & Gas Operator | Aug 2017 |
| 13 | Texas Royalty Corp. | Austin, TX 78746 | Oil & Gas Operator | Feb 2026 |
| 14 | Texzona Oil & Gas, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Dec 1997 |
| 15 | Third Coast Energy, Inc. | Corpus Chrsti, TX 78427 | Oil & Gas Operator | Feb 2026 |
| 16 | Thomas Exploration & Devel., Inc | Jourdanton, TX 78026 | Oil & Gas Operator | Feb 2026 |
| 17 | Thomas Oil And Gas Inc. | San Angelo, TX 76906 | Oil & Gas Operator | May 2019 |
| 18 | Thompson, J. Cleo | Dallas, TX 75201 | Oil & Gas Operator | May 2024 |
| 19 | Thompson, Richard W. Inc. | Plano, TX 75024 | Oil & Gas Operator | Feb 2026 |
| 20 | THP Operating LLC | Santa Anna, TX 76878 | Oil & Gas Operator | Feb 2026 |
| 21 | Three Rivers Operating Co LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 22 | Tidal Petroleum, Inc. | Schertz, TX 78154 | Oil & Gas Operator | Feb 2026 |
| 23 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 24 | Toc Energy Resources, LLC | Fort Worth, TX 76101 | Oil & Gas Operator | Feb 2026 |
| 25 | Tracer Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Feb 2026 |
| 26 | Tracker Mineral | Clyde, TX 79510 | Oil & Gas Operator | Feb 2026 |
| 27 | Tradition Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2014 |
| 28 | Tradition Resources Oper, LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2017 |
| 29 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Feb 2026 |
| 30 | Triag Energy Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2014 |
| 31 | Triple G Oil & Gas | Sonora, TX 76950 | Oil & Gas Operator | Oct 2022 |
| 32 | TS Oil, LLC | Fort Worth, TX 76114 | Oil & Gas Operator | Feb 2026 |
| 33 | Tucker Drilling Company, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Jul 1996 |
| 34 | Tug Hill Operating, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Dec 2021 |
| 35 | TXP, Incorporated | San Angelo, TX 76906 | Oil & Gas Operator | Feb 2026 |