| 1 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Feb 2026 |
| 2 | Tanglewood Production | Breckenridge, TX 76424 | Oil & Gas Operator | May 2009 |
| 3 | Targa Midstream Services LLC | Houston, TX 77002 | Oil Operator | Mar 2023 |
| 4 | Taurus Operating, Inc. | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 5 | TCS Petroleum Co., LLC | Abilene, TX 79608 | Oil & Gas Operator | Feb 2026 |
| 6 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Feb 2026 |
| 7 | Tenison Oil Company | Abilene, TX 79605 | Oil & Gas Operator | Nov 2025 |
| 8 | Thompson, Richard W. Inc. | Plano, TX 75024 | Oil & Gas Operator | Feb 2026 |
| 9 | Thorp Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2014 |
| 10 | Threshold Development Company | Fort Worth, TX 76109 | Oil & Gas Operator | Aug 2016 |
| 11 | Tiki Oil & Gas, LLC | Cisco, TX 76437 | Oil & Gas Operator | Feb 2026 |
| 12 | Tipperary Oil & Gas Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2014 |
| 13 | Townsend Company | Abilene, TX 79608 | Oil & Gas Operator | Dec 2021 |
| 14 | Tracer Energy, Inc. | Graham, TX 76450 | Oil & Gas Operator | Nov 1998 |
| 15 | Triad Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Oct 2011 |
| 16 | Triangle P Development Corp. | Bronte, TX 76933 | Oil & Gas Operator | Feb 2026 |
| 17 | Tucker Drilling Company, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Jul 1996 |
| 18 | Turner, D. Ann Garrett, Est. Of | Big Spring, TX 79721 | Oil & Gas Operator | Jan 1999 |
| 19 | Tuthill & Barbee | Amarillo, TX 79101 | Oil & Gas Operator | Nov 1994 |