| 1 | T & T Production Co. | Victoria, TX 77902 | Oil & Gas Operator | Feb 1995 |
| 2 | Tana Oil And Gas Corporation | Irving, TX 75062 | Oil & Gas Operator | Mar 2000 |
| 3 | Taurus Minerals, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 4 | TC Oil And Gas, LLC | Denton, TX 76205 | Oil Operator | Mar 2025 |
| 5 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Mar 2025 |
| 6 | Teal Energy USA, Inc. | Houston, TX 77057 | Oil & Gas Operator | Mar 2025 |
| 7 | Tempest Energy Resources, LP | Houston, TX 77251 | Oil & Gas Operator | Jun 2013 |
| 8 | Teon Management, LLC | Midland, TX 79704 | Oil & Gas Operator | Mar 2020 |
| 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 | Mar 2025 |
| 13 | Texas Independent Explor LTD. | Houston, TX 77024 | Oil & Gas Operator | Mar 2025 |
| 14 | Texas Independent Explor., Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2002 |
| 15 | Texas Petroleum Investment Company | Houston, TX 77057 | Oil & Gas Operator | Mar 2025 |
| 16 | Texas Royalty Corp. | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 17 | Texas Southern Petroleum Corp. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Mar 2025 |
| 18 | Texas, Les & Co. | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 19 | Texas, Les C., LTD. | Houston, TX 77095 | Oil & Gas Operator | Dec 2006 |
| 20 | Texco Operating Co. | San Antonio, TX 78209 | Gas Operator | Aug 2003 |
| 21 | Texegy Operating Company LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 22 | Texokan Operating, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2025 |
| 23 | Texstar Petroleum, Inc. | Houston, TX 77002 | Oil & Gas Operator | Nov 2000 |
| 24 | Thorp Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2014 |
| 25 | Three C Exploration, LLC | Hebbronville, TX 78361 | Oil & Gas Operator | Mar 2025 |
| 26 | Three-C Oil And Gas | Hebbronville, TX 78361 | Oil & Gas Operator | Mar 2025 |
| 27 | Thunder Oil & Gas, LLC | Ardmore, OK 73402 | Oil & Gas Operator | Dec 2024 |
| 28 | Tidal Petroleum, Inc. | Schertz, TX 78154 | Oil & Gas Operator | Mar 2025 |
| 29 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Mar 2025 |
| 30 | Trace Operating, LLC | Fort Worth, TX 76116 | Oil & Gas Operator | Mar 2025 |
| 31 | Tracer Energy, Inc. | Graham, TX 76450 | Oil & Gas Operator | Nov 1998 |
| 32 | Tracker Oil & Gas, Inc. | Bastrop, TX 78602 | Oil & Gas Operator | Mar 2025 |
| 33 | Trans-Pecos Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Mar 2025 |
| 34 | Trans-Tex Operating LLC | Dallas, TX 75367 | Oil & Gas Operator | Mar 2025 |
| 35 | Transtexas Gas Corporation | Houston, TX 77265 | Oil & Gas Operator | Aug 2005 |
| 36 | Tri-C Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Aug 2009 |
| 37 | Tri-Union Development Corp. | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 38 | Triad Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Oct 2011 |
| 39 | Triangle Three Resources L.L.C. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2025 |
| 40 | Trident Corporation | Woodsboro, TX 78393 | Oil & Gas Operator | Mar 2025 |
| 41 | Trinity Gas Corporation | Edmond, OK 73003 | Oil & Gas Operator | Mar 2025 |
| 42 | Triple L Oil Company | Corpus Chrsti, TX 78469 | Oil & Gas Operator | Jan 1998 |
| 43 | Tristar Oil & Gas | Freer, TX 78357 | Oil & Gas Operator | Mar 2025 |
| 44 | Trium Energy, Inc. | Laredo, TX 78041 | Gas Operator | Jul 2011 |
| 45 | Trium, LTD. | Laredo, TX 78041 | Oil Operator | Mar 2025 |
| 46 | Truth Resources LP | Houston, TX 77090 | Oil Operator | Sep 2021 |
| 47 | Tschoepe, Arthur J. | Leakey, TX 78873 | Oil & Gas Operator | Jun 2001 |
| 48 | Tucker Operating Co., Inc. | Victoria, TX 77903 | Oil & Gas Operator | Mar 2025 |
| 49 | TX Petroleum Company | Corpus Chrsti, TX 78412 | Oil & Gas Operator | Apr 1996 |