| 401 | Sojourner Drilling Corporation | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 402 | Sounion Petroleum Incorporated | Baltimore, MD 21218 | Oil & Gas Operator | Aug 1994 |
| 403 | Southern Alliance Oil Corp. | Grapevine, TX 76099 | Oil & Gas Operator | Jul 2025 |
| 404 | Southern Union Exploration Co. | Austin, TX 78701 | Oil & Gas Operator | Feb 2002 |
| 405 | Southlake Exploration, Inc. | Southlake, TX 76092 | Oil & Gas Operator | Jul 2025 |
| 406 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 407 | Spalding Energy, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 408 | Spence Energy Company | Dallas, TX 75360 | Oil & Gas Operator | Jul 2025 |
| 409 | Spenergy Corp. | Midland, TX 79701 | Oil & Gas Operator | Dec 1999 |
| 410 | SRG Oil Corporation | Abilene, TX 79604 | Oil & Gas Operator | Apr 1994 |
| 411 | St. Clair Energy Corporation | Tulsa, OK 74153 | Oil & Gas Operator | Mar 2008 |
| 412 | Star Production, Inc. | Dallas, TX 75360 | Oil & Gas Operator | Jul 2025 |
| 413 | Startex Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Jul 2025 |
| 414 | Stearns Operating Company | Abilene, TX 79604 | Oil & Gas Operator | Oct 1993 |
| 415 | Stephens Exploration, Inc. | Dallas, TX 75367 | Oil & Gas Operator | May 2025 |
| 416 | Strand Energy, L.C. | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 417 | Sundial Resources, Inc. | Graham, TX 76450 | Oil & Gas Operator | Jul 2025 |
| 418 | Sunstone Energy Company | Tulsa, OK 74153 | Oil & Gas Operator | Aug 2009 |
| 419 | Susanna Corporation | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2025 |
| 420 | Sutton Oil Co. | Austin, TX 78728 | Oil & Gas Operator | Jul 2025 |
| 421 | Sweetwater Drilling Co., Inc. | Fort Worth, TX 76116 | Oil & Gas Operator | Jul 2025 |
| 422 | Sweetwater Production, Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Jul 2025 |
| 423 | T.O.I. | Midland, TX 79710 | Oil & Gas Operator | Mar 2001 |
| 424 | Tahoe Exploration Inc. | Abilene, TX 79608 | Oil & Gas Operator | Mar 2016 |
| 425 | Tamarack Petroleum Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 426 | Taurus Operating, Inc. | Midland, TX 79710 | Oil & Gas Operator | Jul 2025 |
| 427 | TC Energy LLC | Covington, OK 73730-2116 | Oil & Gas Operator | Sep 2014 |
| 428 | TCS Petroleum Co., LLC | Abilene, TX 79608 | Oil & Gas Operator | Jul 2025 |
| 429 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 430 | Teague Operating Co. | Mabank, TX 75147 | Oil & Gas Operator | Jul 1995 |
| 431 | Terrace Petroleum Corporation | Midland, TX 79701 | Oil & Gas Operator | Jul 2013 |
| 432 | Terrell Oil & Gas Production Co. | Hamlin, TX 79520 | Oil & Gas Operator | Jul 2025 |
| 433 | Tex-Ann Oil & Gas Services, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Jul 2025 |
| 434 | Tex-Atic Resources, Inc. | S. Lake Tahoe, CA 96150 | Oil & Gas Operator | Jul 2025 |
| 435 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Jul 2025 |
| 436 | Texas Pharchem Inc. | Abilene, TX 79601 | Oil & Gas Operator | Apr 2019 |
| 437 | Texical, Inc. | Katy, TX 77491 | Oil & Gas Operator | Jul 2025 |
| 438 | Texoma Oil Tools, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2025 |
| 439 | Texstar North America, Inc. | Waynesboro, MS 39367 | Oil & Gas Operator | Aug 1994 |
| 440 | Texxol Operating Company, Inc. | Fort Worth, TX 76108 | Oil & Gas Operator | Jul 2025 |
| 441 | Texzona Oil & Gas, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Dec 1997 |
| 442 | Thompson, Richard W. Inc. | Plano, TX 75024 | Oil & Gas Operator | Jul 2025 |
| 443 | Threshold Development Company | Fort Worth, TX 76109 | Oil & Gas Operator | Aug 2016 |
| 444 | Tiburon Oil & Gas, Inc. | Midland, TX 79701 | Oil & Gas Operator | Aug 2000 |
| 445 | Titan Energy, Inc. | Austin, TX 78703 | Oil & Gas Operator | Jul 2025 |
| 446 | Townsend Company | Abilene, TX 79608 | Oil & Gas Operator | Dec 2021 |
| 447 | Tuthill & Barbee | Amarillo, TX 79101 | Oil & Gas Operator | Nov 1994 |
| 448 | Txu Lone Star Pipeline | Dallas, TX 75201 | Oil & Gas Operator | Oct 2003 |
| 449 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 450 | United States Gypsum Co | Oakfield, NY 14125 | Oil & Gas Operator | Dec 2024 |
| 451 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jul 2025 |
| 452 | V-F Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 453 | Van Operating, LTD. | Albany, TX 76430 | Oil & Gas Operator | Jul 2025 |
| 454 | Veneto Exploration, LLC | Richardson, TX 75083 | Oil & Gas Operator | Jul 2025 |
| 455 | Viathon Hydrocarbons, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Oct 2020 |
| 456 | Vista Resources, Inc. (A) | Midland, TX 79701 | Oil & Gas Operator | Feb 2000 |
| 457 | VX Operating, LLC | Abilene, TX 79605 | Oil & Gas Operator | Jul 2025 |
| 458 | W.H.D., Inc. | Euless, TX 76039 | Oil & Gas Operator | Aug 1998 |
| 459 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Jul 2025 |
| 460 | Walsh Resources, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Jul 2025 |
| 461 | Walter Exploration Company | Dallas, TX 75206 | Oil & Gas Operator | Jul 2025 |
| 462 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 463 | Walter Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 464 | Walton Producing Company | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2005 |
| 465 | Walton Producing Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2025 |
| 466 | Weakland Investments, Inc. | Denver, CO 80215 | Oil & Gas Operator | Jul 2025 |
| 467 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 468 | Westico Energy Co. | Abilene, TX 79605 | Oil & Gas Operator | Nov 2004 |
| 469 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 470 | Westwood Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | May 2013 |
| 471 | White Wing Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2012 |
| 472 | White, Frank | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 473 | Wilbanks, Bruce A. Company | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 474 | Winchester Energy Operating Co. | Austin, TX 78746 | Oil & Gas Operator | Jul 2025 |
| 475 | Winn Operating, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 476 | WJC, Inc. | Post, TX 79356 | Oil & Gas Operator | Jul 2025 |
| 477 | WTG Exploration | Midland, TX 79705 | Oil & Gas Operator | Jul 2025 |
| 478 | WVH Operating LLC | Aledo, TX 76008 | Oil Operator | Jul 2025 |
| 479 | Xeric Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Jul 1997 |
| 480 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 481 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 482 | Young Marshall R Oil Co | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2011 |
| 483 | Young, Clint Inc. | Graham, TX 76450 | Oil & Gas Operator | Jul 2025 |
| 484 | Zachry Oil And Gas Properties | Midland, TX 79708 | Oil & Gas Operator | Jul 2025 |
| 485 | Zzron Inc. | Midland, TX 79704 | Oil & Gas Operator | Aug 2003 |