| 1 | Tellus Operating Group, LLC | | Oil & Gas Operator | Sep 2025 |
| 2 | Tesla Resources, Inc. | | Oil & Gas Operator | Aug 1996 |
| 3 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 4 | Texada Resources, Inc. | | Oil & Gas Operator | Dec 1992 |
| 5 | Texakoma Operating, L.P. | Plano, TX 75024 | Oil & Gas Operator | Mar 2025 |
| 6 | Texas Crude, Inc. | Houston, TX 77256 | Oil & Gas Operator | Oct 1995 |
| 7 | Texas Gas Exploration Corp. | | Oil & Gas Operator | Nov 1986 |
| 8 | Texas Meridian Operating Co. Inc | Houston, TX 77079 | Oil & Gas Operator | Oct 1993 |
| 9 | Texas Petroleum Investment Company | Houston, TX 77057 | Oil & Gas Operator | Dec 2025 |
| 10 | Texoil Company | | Oil & Gas Operator | Dec 2000 |
| 11 | The Ballard & Cordell Corp | | Oil & Gas Operator | Feb 1982 |
| 12 | The George R Brown Partnership | | Oil & Gas Operator | Jun 1992 |
| 13 | The Meridian Res. & Exp. LLC | | Oil & Gas Operator | Sep 2010 |
| 14 | The Meridian Resource & Exp Co | | Oil & Gas Operator | Dec 2000 |
| 15 | Tipco | Shreveport, LA 71104-3047 | Oil & Gas Operator | May 1988 |
| 16 | Tipperary Oil & Gas Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2014 |
| 17 | TMR Exploration, Inc. | Bossier City, LA 71171 | Oil & Gas Operator | Dec 2025 |
| 18 | Toce Oil Company | | Oil & Gas Operator | Dec 2014 |
| 19 | Total Minatome Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 1998 |
| 20 | Trace Operators, Inc. | | Oil & Gas Operator | Nov 2024 |
| 21 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |