| 501 | Star Production, Inc. | Dallas, TX 75360 | Oil & Gas Operator | Apr 2024 |
| 502 | Startex Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Apr 2024 |
| 503 | Stonebriar Oil LLC | Frisco, TX 75034 | Oil & Gas Operator | Apr 2024 |
| 504 | Stovall Operating Co. | Graham, TX 76450 | Oil & Gas Operator | Apr 2024 |
| 505 | Strand Energy, L.C. | Houston, TX 77002 | Oil & Gas Operator | Apr 2024 |
| 506 | Sun-Key Oil Co., Inc. | Dublin, TX 76446 | Oil & Gas Operator | Apr 2024 |
| 507 | Sundance Consulting Corp. | Abilene, TX 79605 | Oil & Gas Operator | Apr 2024 |
| 508 | Sundial Resources, Inc. | Graham, TX 76450 | Oil & Gas Operator | Apr 2024 |
| 509 | Susanna Corporation | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2024 |
| 510 | Sutton Oil Co. | Austin, TX 78728 | Oil & Gas Operator | Apr 2024 |
| 511 | Swaringin, Howard Operating | Maryneal, TX 79535 | Oil & Gas Operator | May 2003 |
| 512 | Sweet Crude Operating LLC | Brenham, TX 77834 | Oil & Gas Operator | Apr 2024 |
| 513 | Sweetwater Drilling Co., Inc. | Fort Worth, TX 76116 | Oil & Gas Operator | Apr 2024 |
| 514 | T-N-T Engineering, Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Apr 2024 |
| 515 | Tahoe Exploration Inc. | Abilene, TX 79608 | Oil & Gas Operator | Mar 2016 |
| 516 | Talon Production, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Apr 2024 |
| 517 | Taurus Exploration U.S.A., Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 1998 |
| 518 | Taylor, Ben J. Inc. | Fort Worth, TX 76185 | Oil & Gas Operator | Feb 2022 |
| 519 | Taylor-McIlhenny Oper. Co., Inc. | Lewisville, TX 75029 | Oil & Gas Operator | Jan 1996 |
| 520 | TCS Petroleum Co., LLC | Abilene, TX 79608 | Oil & Gas Operator | Apr 2024 |
| 521 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Apr 2024 |
| 522 | Telesis Operating Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Apr 2024 |
| 523 | Tema Oil And Gas Company | Houston, TX 77084 | Oil & Gas Operator | Apr 2024 |
| 524 | Tema Oil And Gas, LLC | Houston, TX 77040 | Oil & Gas Operator | Apr 2000 |
| 525 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Apr 2024 |
| 526 | Texaco Exploration & Prod | Midland, TX 79702 | Oil & Gas Operator | Aug 2002 |
| 527 | Texakoma E & P, LLC | Plano, TX 75024 | Oil & Gas Operator | Apr 2024 |
| 528 | Texakoma Oil & Gas Corp | Dallas, TX 75240 | Oil & Gas Operator | Sep 2014 |
| 529 | Texas Crude Operator, Inc. | Houston, TX 77098 | Oil & Gas Operator | Aug 2017 |
| 530 | Texas United Geoproduction, Inc. | Abilene, TX 79606 | Oil & Gas Operator | Apr 2024 |
| 531 | Texland Petroleum Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2007 |
| 532 | Texona Petroleum Corporation | Houston, TX 77084 | Oil & Gas Operator | Aug 2003 |
| 533 | Texstar North America, Inc. | Waynesboro, MS 39367 | Oil & Gas Operator | Aug 1994 |
| 534 | Texzona Oil & Gas, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Dec 1997 |
| 535 | Thompson, Richard W. Inc. | Plano, TX 75024 | Oil & Gas Operator | Apr 2024 |
| 536 | Three Rivers Operating Co LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 537 | Tidmore, Ann | Albany, TX 76430 | Oil & Gas Operator | Apr 2024 |
| 538 | Titan Energy, Inc. | Austin, TX 78703 | Oil & Gas Operator | Apr 2024 |
| 539 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Apr 2024 |
| 540 | Toreador Exploration & Prod Inc | Dallas, TX 75240 | Oil & Gas Operator | Feb 2008 |
| 541 | Trans Oil Marketing LLC | Abilene, TX 79602 | Oil Operator | Aug 2023 |
| 542 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Apr 2024 |
| 543 | Trey Exploration, Inc. | San Angelo, TX 76901 | Oil & Gas Operator | Dec 2020 |
| 544 | Tri-Tex Exploration LTD | Abilene, TX 79608 | Oil Operator | Apr 2019 |
| 545 | Triangle P Development Corp. | Bronte, TX 76933 | Oil & Gas Operator | Apr 2024 |
| 546 | Trilogy Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Apr 2024 |
| 547 | Triple T Resources, LP | Dallas, TX 75205 | Oil & Gas Operator | Dec 2023 |
| 548 | Tripower Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2020 |
| 549 | Triton Operating LLC | Wichita Falls, TX 76310 | Oil & Gas Operator | Apr 2024 |
| 550 | Tucker Drilling Company, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Jul 1996 |
| 551 | Tuthill & Barbee | Amarillo, TX 79101 | Oil & Gas Operator | Nov 1994 |
| 552 | U S Energy Corp. Of Amer. Inc. | Ranger, TX 76470 | Oil & Gas Operator | Apr 2024 |
| 553 | Ultra Oil & Gas, Inc. | Centerton, AR 72719 | Oil & Gas Operator | Apr 2024 |
| 554 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 555 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2024 |
| 556 | United Energy Trading LLC | Tulsa, OK 74133 | Gas Operator | Feb 2015 |
| 557 | United Operating, LLC *** | Midland, TX 79710 | Oil & Gas Operator | Apr 2024 |
| 558 | V-F Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2024 |
| 559 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Apr 2024 |
| 560 | Van Operating, LTD. | Albany, TX 76430 | Oil & Gas Operator | Apr 2024 |
| 561 | Vanco Oil & Gas Corp. | Abilene, TX 79604 | Oil & Gas Operator | Apr 2024 |
| 562 | Vanguard Production Company | Lubbock, TX 79410 | Oil & Gas Operator | Apr 2024 |
| 563 | Vaughn Petroleum, Inc. | Dallas, TX 75219 | Oil & Gas Operator | May 2004 |
| 564 | Veneto Exploration, LLC | Plano, TX 75074 | Oil & Gas Operator | Apr 2024 |
| 565 | Ventex Operating Corp. | Addison, TX 75001 | Oil & Gas Operator | Apr 2024 |
| 566 | Viathon Hydrocarbons, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Oct 2020 |
| 567 | Viejo Services, LLC | Boyd, TX 76023 | Oil & Gas Operator | Apr 2024 |
| 568 | Vision Minerals, LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |
| 569 | Vista Resources, Inc. (A) | Midland, TX 79701 | Oil & Gas Operator | Feb 2000 |
| 570 | VX Operating, LLC | Abilene, TX 79605 | Oil & Gas Operator | Apr 2024 |
| 571 | W & W Production, LLC | Wichita Falls, TX 76308 | Oil Operator | Apr 2024 |
| 572 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 573 | Walbet, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Apr 2024 |
| 574 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Apr 2024 |
| 575 | Walsh Resources, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Apr 2024 |
| 576 | Walter Exploration Company | Dallas, TX 75206 | Oil & Gas Operator | Apr 2024 |
| 577 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 578 | Walton Producing Company | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2005 |
| 579 | Walton, W. W. | Breckenridge, TX 76424 | Oil & Gas Operator | Sep 1994 |
| 580 | Watco Energy, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Apr 1996 |
| 581 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 582 | West Inland Energy, Inc. | Aledo, TX 76008 | Oil & Gas Operator | Apr 2024 |
| 583 | Western Sky Oil & Gas | Abilene, TX 79604 | Oil & Gas Operator | Aug 2003 |
| 584 | Westland Oil Development Corp. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2008 |
| 585 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Feb 2024 |
| 586 | Westwin Energy I, LP | Midland, TX 79701 | Oil & Gas Operator | Aug 2003 |
| 587 | Westwood Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | May 2013 |
| 588 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2024 |
| 589 | Williams Oil Company | Midland, TX 79710 | Oil & Gas Operator | Apr 2024 |
| 590 | Williams, A. Oil | Wichita Falls, TX 76308 | Oil Operator | Apr 2024 |
| 591 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2024 |
| 592 | Wilson Brothers Leasing Co., Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2015 |
| 593 | Wilson Energy LLC | Marietta, OH 45750 | Oil & Gas Operator | Dec 2023 |
| 594 | Wilson Exploration Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 1996 |
| 595 | Wilson, W. Corp. | Midland, TX 79705 | Oil & Gas Operator | Mar 1999 |
| 596 | Wilson, WM. B. Exploration Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 1996 |
| 597 | Winchester Energy, LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 598 | Wiser Oil Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2019 |
| 599 | Wolverine Exploration Company | Houston, TX 77002 | Oil & Gas Operator | May 2019 |
| 600 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |