| 401 | STZ Petroleum Inc. | Houston, TX 77268 | Oil & Gas Operator | Dec 1997 |
| 402 | Sugar Creek Producing Company | | Oil & Gas Operator | Dec 2010 |
| 403 | Sugar Creek Producing Company, LLC | | Oil & Gas Operator | Jan 2025 |
| 404 | Sun Exploration-Production Co. | | Oil & Gas Operator | Jan 1990 |
| 405 | Sunland Production Company, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jun 2025 |
| 406 | Superior Oil Co. | Denver, CO 80217-5444 | Oil & Gas Operator | Feb 2001 |
| 407 | Sutton-Gerard Et Al | | Oil & Gas Operator | Jan 1990 |
| 408 | Sutton-Gerard-Sawyer | | Oil & Gas Operator | Jan 1990 |
| 409 | Sutton-Sawyer | | Oil Operator | Mar 1989 |
| 410 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 411 | T. L. James & Co., Inc. | | Oil & Gas Operator | Oct 1992 |
| 412 | T.O.I. | Midland, TX 79710 | Oil & Gas Operator | Mar 2001 |
| 413 | Tanner Oil, Inc | | Oil & Gas Operator | Nov 2024 |
| 414 | Tanos Exploration II, LLC | Tyler, TX 75701 | Oil & Gas Operator | Sep 2023 |
| 415 | TDX Energy, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2024 |
| 416 | Tellus Operating Group, LLC | | Oil & Gas Operator | Jun 2025 |
| 417 | Tenison Oil Company | Abilene, TX 79605 | Oil & Gas Operator | Jun 2025 |
| 418 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Jul 2025 |
| 419 | Tensas Delta Expl Co., LLC | Shreveport, LA 71101-5323 | Oil & Gas Operator | Jul 2021 |
| 420 | Terrier Oil Company | | Oil & Gas Operator | Feb 2015 |
| 421 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Oct 2025 |
| 422 | Texaco Oils, Inc. | Tulsa, OK 74102-2420 | Oil & Gas Operator | Jan 2003 |
| 423 | Texaco Producing Inc. | Rock Springs, WY 82901 | Oil & Gas Operator | Dec 2000 |
| 424 | Texas Eastern Transm. Corp. | | Oil & Gas Operator | Dec 2002 |
| 425 | Texas Gas Transmission Corp. | | Oil Operator | Aug 2003 |
| 426 | Texas Gas Transmission LLC | Owensboro, KY 42301 | Oil & Gas Operator | Dec 2024 |
| 427 | Texas Oil & Gas Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 428 | Texstar Petroleum, Inc. | Houston, TX 77002 | Oil & Gas Operator | Nov 2000 |
| 429 | TGNR TVL LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 430 | TGX Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2004 |
| 431 | The Blackbird Company | Shreveport, LA 71106 | Oil & Gas Operator | Jan 2025 |
| 432 | The Maurice L. Brown Company | | Oil & Gas Operator | Aug 1987 |
| 433 | Tideway Oil Programs, Inc. | | Oil & Gas Operator | Oct 1980 |
| 434 | Tipco | Shreveport, LA 71104-3047 | Oil & Gas Operator | May 1988 |
| 435 | TMR Exploration, Inc. | Bossier City, LA 71171 | Oil & Gas Operator | Oct 2025 |
| 436 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Oct 2025 |
| 437 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 438 | Total E&P USA, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 2025 |
| 439 | Total Minatome Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 1998 |
| 440 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 441 | Trafalgar House Oil & Gas Inc. | Houston, TX 77002-7346 | Oil & Gas Operator | Jan 1992 |
| 442 | Trans-Western Expl. Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 1993 |
| 443 | Trinidad Petroleum Corporation | | Oil & Gas Operator | Apr 1990 |
| 444 | Triton Oil & Gas Corp. | Houston, TX 77002 | Oil & Gas Operator | Nov 2014 |
| 445 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 446 | TXP Operating Company | | Oil & Gas Operator | Jul 1992 |
| 447 | Ty-Tex Exploration, Inc. | Tyler, TX 75711 | Oil Operator | Dec 2000 |
| 448 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 449 | United Gas Pipe Line Co. | | Oil Operator | Aug 1993 |
| 450 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 451 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Oct 2025 |
| 452 | Vanguard Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Feb 2021 |
| 453 | Vaughn Petroleum, Inc. | Dallas, TX 75219 | Oil & Gas Operator | May 2004 |
| 454 | Vector Energy Corporation | Houston, TX 77060 | Oil & Gas Operator | Oct 2025 |
| 455 | Vega Oil & Gas MGMT., Inc. | | Oil & Gas Operator | Aug 1981 |
| 456 | Velandera Energy Partners LLC | | Oil & Gas Operator | Nov 2024 |
| 457 | Verado Energy, Inc. | Allen, TX 75013 | Oil & Gas Operator | Oct 2025 |
| 458 | Vernon E. Faulconer, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Dec 2024 |
| 459 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 460 | Vista Corporation | | Oil & Gas Operator | Jan 2011 |
| 461 | Vista Resources LLC | Teague, TX 75860 | Oil & Gas Operator | Oct 2025 |
| 462 | W. A. Moncrief | | Oil & Gas Operator | Jun 2010 |
| 463 | W. A. Stanberry | | Oil & Gas Operator | Nov 1988 |
| 464 | W. Harlan Beene | | Oil Operator | Jan 2025 |
| 465 | Wagon Wheel Arklatex, LLC | | Oil & Gas Operator | May 2018 |
| 466 | Walker Energy, LLC | | Oil & Gas Operator | Nov 2024 |
| 467 | Watchtower Petroleum, LLC | | Oil & Gas Operator | Jun 2025 |
| 468 | Wayne J. Spears | | Oil & Gas Operator | Sep 2005 |
| 469 | Weiser-Brown Operating Company | Magnolia, AR 71754 | Oil & Gas Operator | Oct 2025 |
| 470 | Wheless Industries, Inc. | Shreveport, LA 71101-5301 | Oil & Gas Operator | Sep 2002 |
| 471 | Wheless Industries-Pelto Oil | | Oil & Gas Operator | Dec 1989 |
| 472 | White & Bancroft Et Al | | Oil Operator | Jan 1996 |
| 473 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 474 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 475 | Whitton Company, Inc. | | Oil & Gas Operator | Jul 2020 |
| 476 | Wilcox Operating Corporation | Shreveport, LA 71115 | Oil & Gas Operator | Oct 2025 |
| 477 | Wildhorse Resources Management Co, LLC | | Oil & Gas Operator | Feb 2018 |
| 478 | Wildhorse Resources, LLC | Houston, TX 77279 | Oil & Gas Operator | Feb 2015 |
| 479 | Will Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2025 |
| 480 | Will-Drill Operating, L.L.C. | Shreveport, LA 71105 | Oil & Gas Operator | Oct 2025 |
| 481 | Will-Drill Production Co., Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Oct 2025 |
| 482 | Williamson & Smitherman | | Oil & Gas Operator | Dec 2008 |
| 483 | Williamson Oil & Gas, Inc. | Shreveport, LA 71166 | Oil & Gas Operator | Dec 2024 |
| 484 | Willow Springs Production, Inc. | Longview, TX 75606 | Oil & Gas Operator | Sep 1999 |
| 485 | Wintershall Corporation | | Oil & Gas Operator | Oct 1989 |
| 486 | Winwell, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2007 |
| 487 | Wisenbaker Production Company | Tyler, TX 75702 | Oil & Gas Operator | Oct 2011 |
| 488 | WM. Herbert Hunt TR.Est. | | Oil & Gas Operator | Oct 1992 |
| 489 | Woodbine Production Corporation | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 490 | Wooldridge Production Co.,LTD. | | Oil & Gas Operator | Apr 2008 |
| 491 | Wooldridge Production, L.L.C. | | Oil Operator | Mar 2005 |
| 492 | WSF, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jun 2013 |
| 493 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 494 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 495 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |