| 601 | Texland-Rector & Schumacher | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2000 |
| 602 | Thompson, J. Cleo | Dallas, TX 75201 | Oil & Gas Operator | May 2024 |
| 603 | Three Rivers Oper Co III LLC | Austin, TX 78735 | Oil & Gas Operator | Nov 2017 |
| 604 | Three Rivers Operating Co LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 605 | Three-B Oil Company, The | Monahans, TX 79756 | Oil & Gas Operator | Jun 2026 |
| 606 | Titan Energy, Inc. | Austin, TX 78703 | Oil & Gas Operator | Jun 2026 |
| 607 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 608 | Titus Oil & Gas Production, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2022 |
| 609 | TMBR/Sharp Drilling, Inc. | Midland, TX 79703 | Oil & Gas Operator | Feb 2004 |
| 610 | Tog Operating, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2026 |
| 611 | Topat Oil Corporation | Midland, TX 79701 | Oil & Gas Operator | Sep 2017 |
| 612 | Trey Resources Inc. | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 613 | Trigo Oil And Gas, LLC | Amarillo, TX 79101 | Oil & Gas Operator | Mar 2022 |
| 614 | Triple "N" Services, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 615 | Triple J Investments Inc | Longview, TX 75606 | Oil & Gas Operator | Feb 2023 |
| 616 | Triumph Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 617 | TRP Operating LLC | Houston, TX 77024 | Oil & Gas Operator | Jun 2026 |
| 618 | TS Oil, LLC | River Oaks, TX 76114 | Oil & Gas Operator | Jun 2026 |
| 619 | Two Black Bears Oil, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2003 |
| 620 | Two Oaks Operating Company, LLC. | Flower Mound, TX 75028 | Oil & Gas Operator | Mar 2008 |
| 621 | U. S. Energy Development Corporation | Fort Worth, TX 76164 | Oil & Gas Operator | Jun 2026 |
| 622 | U. S. Operating, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Jul 2025 |
| 623 | U.S. Sovereign Oil And Gas, Inc. | Dallas, TX 75355 | Oil & Gas Operator | Jun 2026 |
| 624 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 625 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 626 | Upcurve Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Jun 2026 |
| 627 | Upp Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2026 |
| 628 | V-F Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 629 | Vale Petroleum Corporation | Houston, TX 77042 | Gas Operator | Jan 1995 |
| 630 | Vanco Oil & Gas Corp. | Abilene, TX 79604 | Oil & Gas Operator | Jun 2026 |
| 631 | Vanguard Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 632 | Vaquero Gas Company,Incorporated | Houston, TX 77002 | Oil & Gas Operator | Jun 1993 |
| 633 | Vaquero Operating | FT Stockton, TX 79735 | Oil & Gas Operator | Jun 2026 |
| 634 | Veritas Energy LLC | San Antonio, TX 78231 | Oil & Gas Operator | Jun 2026 |
| 635 | Vista Resources, Inc. (A) | Midland, TX 79701 | Oil & Gas Operator | Feb 2000 |
| 636 | Vital Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Jun 2026 |
| 637 | VTX Energy Operating, LLC | Austin, TX 78730 | Oil & Gas Operator | Jun 2026 |
| 638 | Wagner & Brown, LTD. | Midland, TX 79702 | Oil & Gas Operator | Aug 2014 |
| 639 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Jun 2026 |
| 640 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 641 | Warrior Exploration LLC | Sapulpa, OK 74067-1912 | Oil & Gas Operator | Mar 2026 |
| 642 | Waterbridge Texas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Jun 2026 |
| 643 | Watson Packer Employee Fund | Monahans, TX 79756 | Oil & Gas Operator | Jun 2026 |
| 644 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 645 | West Texas Exploration Co. | Graham, TX 76450 | Oil & Gas Operator | May 1996 |
| 646 | Western Disposal Systems, Inc. | Corrales, NM 87048 | Oil Operator | Jun 2026 |
| 647 | Western Global Oil, Inc | Deerfld Beach, FL 33442 | Oil Operator | Jun 2026 |
| 648 | Western Plains Resources LLC | Garden City, KS 67846 | Oil & Gas Operator | Feb 2026 |
| 649 | Western Reserves Oil Co Inc | Midland, TX 79705 | Oil & Gas Operator | Oct 2020 |
| 650 | Westridge Oil & Gas Properties | Mineral Wells, TX 76068 | Oil & Gas Operator | Jun 2026 |
| 651 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Mar 2026 |
| 652 | White'S Industrial Engine'S | Houston, TX 77070 | Oil & Gas Operator | Jun 2026 |
| 653 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2026 |
| 654 | Williams Oil Company | Midland, TX 79710 | Oil & Gas Operator | Jun 2026 |
| 655 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Jun 2026 |
| 656 | Williamson, J. C. | Midland, TX 79701 | Oil & Gas Operator | Jan 2001 |
| 657 | Williamson, Ralph E. | Midland, TX 79702 | Oil & Gas Operator | Jan 2012 |
| 658 | Wilson Exploration Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 1996 |
| 659 | Wind River Resources Inc | Tulsa, OK 74136-6381 | Oil & Gas Operator | Jun 2010 |
| 660 | Wiser Oil Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2023 |
| 661 | Wolf Energy | Midland, TX 79701 | Oil & Gas Operator | Jan 1995 |
| 662 | Wolf Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2021 |
| 663 | Wood, McShane & Thams | Midland, TX 79702 | Oil & Gas Operator | Oct 1995 |
| 664 | WPX Energy Permian, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2026 |
| 665 | WTG Exploration Inc | Midland, TX 79705 | Oil & Gas Operator | Dec 2023 |
| 666 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 667 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 668 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jun 2026 |
| 669 | Yarborough Oil & Gas L.P. | Midland, TX 79701 | Oil & Gas Operator | Oct 2000 |
| 670 | Yates Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 671 | Yates, Harvey E. Company | Roswell, NM 88201 | Oil & Gas Operator | Dec 2002 |