| 1 | T. C. Morrow Oil Co. | | Oil & Gas Operator | Apr 1991 |
| 2 | T. L. James & Co., Inc. | | Oil & Gas Operator | Oct 1992 |
| 3 | TDX Energy, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2024 |
| 4 | Tensas Delta Expl Co., LLC | Shreveport, LA 71101-5323 | Oil & Gas Operator | Jul 2021 |
| 5 | Tensas Delta Land Company | | Oil & Gas Operator | Apr 2002 |
| 6 | Texas Petroleum Investment Company | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 7 | Thomas Bell | | Oil Operator | Dec 1985 |
| 8 | Thomas G. Easterling | | Oil Operator | Jun 1989 |
| 9 | Thomas Turman | | Oil & Gas Operator | Dec 1991 |
| 10 | Thornton Page Natural Gas | | Oil & Gas Operator | Dec 2024 |
| 11 | THT Operating Company | | Oil & Gas Operator | Jul 1990 |
| 12 | TMR Exploration, Inc. | Bossier City, LA 71171 | Oil & Gas Operator | Oct 2025 |
| 13 | Toc, Inc. (TN) | | Oil Operator | Apr 1995 |
| 14 | Tradestar Energy, Inc. | Hot Springs, AR 71913 | Oil Operator | Feb 2021 |
| 15 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 16 | Tredegar Properties, Inc. | | Oil Operator | Jun 1990 |
| 17 | Trendsetter Production Co, Inc | | Oil & Gas Operator | Jul 2008 |
| 18 | Trich Production, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jan 2025 |
| 19 | Trichel Contracting Company | | Oil & Gas Operator | Sep 1987 |
| 20 | Trident Oil And Gas Corp. | | Oil & Gas Operator | Sep 2000 |
| 21 | Trinidad Petroleum Corporation | | Oil & Gas Operator | Apr 1990 |
| 22 | Triple J Investments Inc | Longview, TX 75606 | Oil & Gas Operator | Feb 2023 |
| 23 | Tundra Energy | | Oil Operator | Jan 2025 |
| 24 | Tundra Operating LLC | Spring, TX 77386 | Oil Operator | May 2017 |
| 25 | TWC Oil Company | | Oil Operator | Jan 2025 |
| 26 | Twiner Oil & Gas Corporation | | Oil & Gas Operator | Oct 1988 |