| 401 | Thomas Exploration & Devel., Inc | Jourdanton, TX 78026 | Oil & Gas Operator | Feb 2026 |
| 402 | Thompson, J. Cleo | Dallas, TX 75201 | Oil & Gas Operator | May 2024 |
| 403 | Three J'S Petroleum, Inc. | Lubbock, TX 79423 | Oil & Gas Operator | Feb 2026 |
| 404 | Three Span Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 405 | Threshold Development Company | Fort Worth, TX 76109 | Oil & Gas Operator | Aug 2016 |
| 406 | Tindle Petroleum LLC | Midland, TX 79701 | Oil & Gas Operator | Jan 2023 |
| 407 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 408 | TNCH, LLC | Colorado City, TX 79512 | Oil Operator | Feb 2026 |
| 409 | Topat Oil Corporation | Midland, TX 79701 | Oil & Gas Operator | Sep 2017 |
| 410 | Tradition Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2014 |
| 411 | Tradition Resources Oper, LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2017 |
| 412 | Travis, J. J., Trustee | Rockport, TX 78382 | Oil & Gas Operator | Dec 1996 |
| 413 | Trek Petroleum Company, Inc. | Midland, TX 79707 | Oil & Gas Operator | Feb 2026 |
| 414 | Trend Exploration Company | Midland, TX 79701 | Oil & Gas Operator | Mar 2008 |
| 415 | Trey Exploration, Inc. | San Angelo, TX 76901 | Oil & Gas Operator | Dec 2020 |
| 416 | Triag Energy Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2014 |
| 417 | Trico Energy LLC | Hager Hill, KY 41222 | Oil Operator | Dec 2018 |
| 418 | Trio Consulting & Management,LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Feb 2026 |
| 419 | Trio Operating Company, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2006 |
| 420 | Tucker Drilling Company, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Jul 1996 |
| 421 | Tuthill & Barbee | Amarillo, TX 79101 | Oil & Gas Operator | Nov 1994 |
| 422 | U.S. Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 423 | Unified Oil & Gas Corp. | Snyder, TX 79550 | Oil Operator | Feb 2026 |
| 424 | United Oil & Shale LLC | Woodward, OK 73801 | Oil & Gas Operator | Feb 2026 |
| 425 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | Feb 2026 |
| 426 | Us Petro LP | Amarillo, TX 79106 | Oil & Gas Operator | Apr 2020 |
| 427 | Vanco Oil & Gas Corp. | Abilene, TX 79604 | Oil & Gas Operator | Feb 2026 |
| 428 | Vector Energy Corporation | Houston, TX 77060 | Oil & Gas Operator | Feb 2026 |
| 429 | Vess Oil Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 430 | Vista Energy Corp. | Good Lettsvle, TN 37072 | Oil & Gas Operator | Feb 2026 |
| 431 | Vtex Energy, Inc. | Houston, TX 77057 | Oil & Gas Operator | Feb 2026 |
| 432 | W & W Properties | Westbrook, TX 79565 | Oil & Gas Operator | Aug 2018 |
| 433 | W.A. Oil Co. | Andrews, TX 79714 | Oil & Gas Operator | Aug 1997 |
| 434 | W.P.P.I. Inc. | Westbrook, TX 79565 | Oil & Gas Operator | Jul 2013 |
| 435 | Wainoco Oil & Gas Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2005 |
| 436 | Walker Oil And Gas LTD | Snyder, TX 79550 | Oil Operator | Feb 2026 |
| 437 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Feb 2026 |
| 438 | Wash, Robert C. | Forsan, TX 79733 | Oil & Gas Operator | Nov 2000 |
| 439 | Wash, Robert C. Inc. | Forsan, TX 79733 | Oil & Gas Operator | Feb 2026 |
| 440 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 441 | Westco Oil Company | Ozona, TX 76943 | Oil & Gas Operator | Feb 2026 |
| 442 | Western DRLG. Co. | Longview, TX 75604 | Oil & Gas Operator | Nov 1996 |
| 443 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2026 |
| 444 | Wilbanks, Bruce & G.L. | Midland, TX 79702 | Oil & Gas Operator | Aug 1996 |
| 445 | Wilbanks, Bruce A. | Midland, TX 79701 | Oil & Gas Operator | Aug 1996 |
| 446 | Wilbanks, Bruce A. Company | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |
| 447 | Wilchar, DR. R. B. | Fort Worth, TX 76185 | Oil & Gas Operator | Jan 2007 |
| 448 | Williams Oil Company | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 449 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Feb 2026 |
| 450 | Windham, L. E. | Rankin, TX 79778 | Oil & Gas Operator | Dec 1996 |
| 451 | Windham, L.E. Estate Of | Midland, TX 79702 | Oil & Gas Operator | Mar 2012 |
| 452 | Wing Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2000 |
| 453 | Winn Operating, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2026 |
| 454 | WJC, Inc. | Post, TX 79356 | Oil & Gas Operator | Feb 2026 |
| 455 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 456 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |