| 1 | Tabco Exploration Inc. | New Orleans, LA 70131 | Oil & Gas Operator | Dec 1998 |
| 2 | Tandem Energy Corporation | Houston, TX 77056 | Oil & Gas Operator | Dec 2024 |
| 3 | Tema Oil And Gas Company | Houston, TX 77084 | Oil & Gas Operator | Dec 2024 |
| 4 | Tema Oil And Gas, LLC | Houston, TX 77040 | Oil & Gas Operator | Apr 2000 |
| 5 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Dec 2024 |
| 6 | Texakota, Inc. | Houston, TX 77098 | Oil & Gas Operator | Mar 2021 |
| 7 | Texas American Resources Company | Austin, TX 78701 | Oil & Gas Operator | Dec 2024 |
| 8 | Texas Crude, Inc. | Houston, TX 77256 | Oil & Gas Operator | Oct 1995 |
| 9 | Texas Oil Company, The | Houston, TX 77018 | Oil & Gas Operator | Aug 2006 |
| 10 | Texas Petroleum Investment Company | Houston, TX 77057 | Oil & Gas Operator | Dec 2024 |
| 11 | Texcal Energy (GP) LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2016 |
| 12 | Texian Operating Company, LLC | Irving, TX 75063 | Oil & Gas Operator | Dec 2024 |
| 13 | TNT Oil Co. | Hamlin, TX 79520 | Oil & Gas Operator | Dec 2024 |
| 14 | Tomlinson, John Oil Operator | Batson, TX 77519 | Oil & Gas Operator | Mar 2008 |
| 15 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 16 | Trans-Pecos Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Dec 2024 |
| 17 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 18 | Transoil, Inc. | Oklahoma City, OK 73129 | Oil & Gas Operator | Dec 2024 |
| 19 | Traton Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Mar 2019 |
| 20 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Dec 2024 |
| 21 | Tri-Union Development Corp. | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 22 | Triangle Three Resources L.L.C. | Dallas, TX 75240 | Oil & Gas Operator | Dec 2024 |
| 23 | Triton Oil & Gas Corp. | Houston, TX 77002 | Oil & Gas Operator | Nov 2014 |
| 24 | True Oil Company | Casper, WY 82602 | Oil & Gas Operator | Aug 2003 |
| 25 | Truth Resources LP | Houston, TX 77090 | Oil Operator | Sep 2021 |