| 1 | Tamarack Petroleum Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 2 | Tara Operating Co. | Lamesa, TX 79331 | Oil & Gas Operator | Aug 2003 |
| 3 | Taurus Exploration U.S.A., Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 1998 |
| 4 | TC Oil And Gas, LLC | Denton, TX 76205 | Oil Operator | Oct 2025 |
| 5 | TCF Energy, Inc. | Midland, TX 79704 | Oil & Gas Operator | Dec 2004 |
| 6 | TD Oil & Gas LLC | Duncan, OK 73533-1851 | Oil Operator | Apr 2023 |
| 7 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 8 | Tejas Operators, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 2003 |
| 9 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Oct 2025 |
| 10 | Texas Crude Operator, Inc. | Houston, TX 77098 | Oil & Gas Operator | Aug 2017 |
| 11 | Texland Petroleum Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2003 |
| 12 | Texland Petroleum, L.P. | Fort Worth, TX 76107 | Oil & Gas Operator | Oct 2025 |
| 13 | Thompson, J. Cleo | Dallas, TX 75201 | Oil & Gas Operator | May 2024 |
| 14 | Three Forks Resources LLC | Wheat Ridge, CO 80033 | Oil & Gas Operator | Oct 2025 |
| 15 | Three Rivers Operating Co II LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 16 | Three Span Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 17 | Tipperary Oil & Gas Corp | Denver, CO 80202 | Oil & Gas Operator | May 2014 |
| 18 | TMBR/Sharp Drilling, Inc. | Midland, TX 79703 | Oil & Gas Operator | Feb 2004 |
| 19 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Oct 2025 |
| 20 | Toreador Exploration & Prod Inc | Dallas, TX 75240 | Oil & Gas Operator | Feb 2008 |
| 21 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Oct 2025 |
| 22 | Trico Energy LLC | Hager Hill, KY 41222 | Oil Operator | Dec 2018 |
| 23 | Trilogy Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Oct 2025 |
| 24 | Trinidad Resources, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2025 |
| 25 | Trinity Bay Oil & Gas, Inc. | Lubbock, TX 79416 | Oil & Gas Operator | Oct 2025 |
| 26 | Trinity Operating & Prod., Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 27 | Trio Operating Company, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2006 |
| 28 | Triple "N" Services, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 29 | Triple T Resources, LP | Dallas, TX 75205 | Oil & Gas Operator | Jun 2025 |
| 30 | Triton Oil & Gas Corp. | Houston, TX 77002 | Oil & Gas Operator | Nov 2014 |