| 1 | T. L. James & Co., Inc. | | Oil & Gas Operator | Oct 1992 |
| 2 | T.O.I. | Midland, TX 79710 | Oil & Gas Operator | Mar 2001 |
| 3 | Tanner Oil, Inc | | Oil & Gas Operator | Nov 2024 |
| 4 | Tanos Exploration II, LLC | Tyler, TX 75701 | Oil & Gas Operator | Sep 2023 |
| 5 | TDX Energy, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2024 |
| 6 | Tellus Operating Group, LLC | | Oil & Gas Operator | Sep 2025 |
| 7 | Tenison Oil Company | Abilene, TX 79605 | Oil & Gas Operator | Aug 2025 |
| 8 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Sep 2025 |
| 9 | Tensas Delta Expl Co., LLC | Shreveport, LA 71101-5323 | Oil & Gas Operator | Jul 2021 |
| 10 | Terrier Oil Company | | Oil & Gas Operator | Feb 2015 |
| 11 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Dec 2025 |
| 12 | Texaco Oils Inc | Tulsa, OK 74102-2420 | Oil & Gas Operator | Jan 2003 |
| 13 | Texaco Producing Inc. | Rock Springs, WY 82901 | Oil & Gas Operator | Dec 2000 |
| 14 | Texas Eastern Transm. Corp. | | Oil & Gas Operator | Dec 2002 |
| 15 | Texas Gas Transmission Corp. | | Oil Operator | Aug 2003 |
| 16 | Texas Gas Transmission, LLC | Owensboro, KY 42301 | Oil & Gas Operator | Dec 2024 |
| 17 | Texas Oil & Gas Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 18 | Texstar Petroleum, Inc. | Houston, TX 77002 | Oil & Gas Operator | Nov 2000 |
| 19 | TGNR TVL LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 20 | TGX Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2004 |
| 21 | The Maurice L. Brown Company | | Oil & Gas Operator | Aug 1987 |
| 22 | Tideway Oil Programs, Inc. | | Oil & Gas Operator | Oct 1980 |
| 23 | Tipco | Shreveport, LA 71104-3047 | Oil & Gas Operator | May 1988 |
| 24 | TMR Exploration, Inc. | Bossier City, LA 71171 | Oil & Gas Operator | Dec 2025 |
| 25 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Dec 2025 |
| 26 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 27 | Total E&P USA, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 2025 |
| 28 | Total Minatome Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 1998 |
| 29 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 30 | Trafalgar House Oil & Gas Inc | Houston, TX 77002-7346 | Oil & Gas Operator | Jan 1992 |
| 31 | Trans-Western Exploration Inc | Dallas, TX 75240 | Oil & Gas Operator | Mar 1993 |
| 32 | Trinidad Petroleum Corporation | | Oil & Gas Operator | Apr 1990 |
| 33 | Triton Oil & Gas Corp. | Houston, TX 77002 | Oil & Gas Operator | Nov 2014 |
| 34 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 35 | TXP Operating Co. | | Oil & Gas Operator | Jul 1992 |
| 36 | Ty-Tex Exploration, Inc. | Tyler, TX 75711 | Oil Operator | Dec 2000 |