| 1 | Tana Oil And Gas Corporation | Irving, TX 75062 | Oil & Gas Operator | Mar 2000 |
| 2 | Tare Resources, LLC | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Dec 2025 |
| 3 | Tasca Exploration Company | Houston, TX 77257 | Oil & Gas Operator | Jun 2002 |
| 4 | TBM Catarina, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2025 |
| 5 | TD Natural Resources LLC | Cuero, TX 77954 | Oil & Gas Operator | Dec 2025 |
| 6 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 7 | Teal Energy USA, Inc. | Houston, TX 77057 | Oil & Gas Operator | Dec 2025 |
| 8 | Tejas Gas Pipeline, L.P. | Houston, TX 77002 | Oil & Gas Operator | Feb 2002 |
| 9 | Tepee Petroleum Company, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 2014 |
| 10 | Tesoro E&P Company, L.P. | San Antonio, TX 78216 | Oil & Gas Operator | Jan 2000 |
| 11 | Tesoro Expl. & Prod. Company | San Antonio, TX 78216 | Gas Operator | Sep 2010 |
| 12 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Dec 2025 |
| 13 | Texan Production | Pearsall, TX 78061 | Oil & Gas Operator | Aug 2003 |
| 14 | Texan Production Company, Inc. | Canyon Lake, TX 78133 | Oil & Gas Operator | Dec 2025 |
| 15 | Texas Crude Energy, Inc. | Houston, TX 77256 | Oil & Gas Operator | Oct 2012 |
| 16 | Texas Independent Explor LTD. | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 17 | Texas, Les & Co. | Brenham, TX 77833 | Oil & Gas Operator | Dec 2025 |
| 18 | Texron Operating, LLC | Bulverde, TX 78163 | Oil & Gas Operator | Dec 2025 |
| 19 | Thorp Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2014 |
| 20 | Three C Exploration, LLC | Hebbronville, TX 78361 | Oil & Gas Operator | Dec 2025 |
| 21 | Three-C Oil And Gas | Hebbronville, TX 78361 | Oil & Gas Operator | Dec 2025 |
| 22 | Tidal Petroleum, Inc. | Schertz, TX 78154 | Oil & Gas Operator | Dec 2025 |
| 23 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 24 | TNR Petroleum, Inc. | Austin, TX 78747 | Oil & Gas Operator | Sep 1999 |
| 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 | Tradition Resources Oper, LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2017 |
| 28 | Trans-Pecos Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 29 | Transamerican Natural Gas Corp. | Houston, TX 77032 | Oil & Gas Operator | Aug 2000 |
| 30 | Transtexas Gas Corporation | Houston, TX 77265 | Oil & Gas Operator | Aug 2005 |
| 31 | Tri-C Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Aug 2009 |
| 32 | Trinity Operating (Usg), LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 33 | Trinity River Energy Oper, LLC | Houston, TX 77008 | Oil & Gas Operator | May 2018 |
| 34 | Tristar Oil & Gas | Freer, TX 78357 | Oil & Gas Operator | Dec 2025 |
| 35 | Trium Energy, Inc. | Laredo, TX 78041 | Gas Operator | Jul 2011 |
| 36 | Trium, LTD. | Laredo, TX 78041 | Oil Operator | Dec 2025 |
| 37 | Troubadour Operating, LLC | Houston, TX 77019 | Oil & Gas Operator | Dec 2025 |
| 38 | TX Petroleum Company | Corpus Chrsti, TX 78412 | Oil & Gas Operator | Apr 1996 |
| 39 | Txco Resources Inc. | San Antonio, TX 78280 | Oil & Gas Operator | Dec 2025 |