| 601 | Texas Energy Trust Company | Midland, TX 79701 | Oil & Gas Operator | Jun 2016 |
| 602 | Texland Petroleum Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2003 |
| 603 | Texland Petroleum, L.P. | Fort Worth, TX 76107 | Oil & Gas Operator | Apr 2026 |
| 604 | Texland-Rector & Schumacher | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2000 |
| 605 | Texon Oil Company, Inc. | Midland, TX 79710 | Oil & Gas Operator | Apr 2023 |
| 606 | Thompson, J. Cleo | Dallas, TX 75201 | Oil & Gas Operator | May 2024 |
| 607 | Three Rivers Operating Co LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 608 | Tidwell Production Company | Sonora, TX 76950 | Oil & Gas Operator | Apr 2026 |
| 609 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 610 | TMBR/Sharp Drilling, Inc. | Midland, TX 79703 | Oil & Gas Operator | Feb 2004 |
| 611 | Tomel Production, LLC | Dallas, TX 75360 | Oil & Gas Operator | Apr 2026 |
| 612 | Topat Oil Corporation | Midland, TX 79701 | Oil & Gas Operator | Sep 2017 |
| 613 | Townsend Company | Abilene, TX 79608 | Oil & Gas Operator | Dec 2021 |
| 614 | Trail Ridge Energy PRTNS II LLC | Grapevine, TX 76051 | Oil & Gas Operator | Jun 2017 |
| 615 | Trenna Oil Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2013 |
| 616 | Tri-C Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Aug 2009 |
| 617 | Trilogy Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Apr 2026 |
| 618 | Trio Consulting & Management,LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2026 |
| 619 | Triple "N" Services, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 620 | Triple Crown Resources, LLC | Dallas, TX 75201 | Oil & Gas Operator | Apr 2026 |
| 621 | Triton Oil & Gas Corp. | Houston, TX 77002 | Oil & Gas Operator | Nov 2014 |
| 622 | Triumph Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 623 | Trojan Oil Company, LLC | Big Lake, TX 76932 | Oil Operator | Apr 2026 |
| 624 | TRP Operating LLC | Houston, TX 77024 | Oil & Gas Operator | Apr 2026 |
| 625 | TSF Operating | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 626 | Turner Production | Big Lake, TX 76932 | Oil & Gas Operator | Apr 2026 |
| 627 | TX Heat Of The Permian Basin Inc | Odessa, TX 79768 | Oil & Gas Operator | Dec 2021 |
| 628 | TXP, Incorporated | San Angelo, TX 76906 | Oil & Gas Operator | Apr 2026 |
| 629 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 630 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 631 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 632 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2026 |
| 633 | United Resources LP | Austin, TX 78746 | Oil & Gas Operator | Oct 2011 |
| 634 | Uplands Resources Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Feb 2026 |
| 635 | Uptex Operating Inc. | Dallas, TX 75201 | Oil & Gas Operator | May 2011 |
| 636 | Uptex Operating, L.P. | Dallas, TX 75201 | Oil & Gas Operator | May 2010 |
| 637 | V-F Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 638 | Valley Resources, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Aug 2003 |
| 639 | Vanguard Permian, LLC | Houston, TX 77057 | Oil & Gas Operator | Nov 2018 |
| 640 | Vencer Energy, LLC | Abilene, TX 79602 | Oil & Gas Operator | Dec 2023 |
| 641 | Verdad Oil & Gas Corporation | Dallas, TX 75235 | Oil & Gas Operator | Jan 2026 |
| 642 | Veritas Energy LLC | San Antonio, TX 78231 | Oil & Gas Operator | Apr 2026 |
| 643 | Viathon Hydrocarbons, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Oct 2020 |
| 644 | Viejo Services, LLC | Boyd, TX 76023 | Oil & Gas Operator | Apr 2026 |
| 645 | Viking Energy Corporation | Odessa, TX 79760 | Oil & Gas Operator | Dec 2021 |
| 646 | Vista Resources, Inc. (A) | Midland, TX 79701 | Oil & Gas Operator | Feb 2000 |
| 647 | Vital Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 648 | Wadi Petroleum Inc | Houston, TX 77014 | Oil & Gas Operator | May 2018 |
| 649 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Apr 2026 |
| 650 | Warrior Exploration LLC | Sapulpa, OK 74067-1912 | Oil & Gas Operator | Feb 2026 |
| 651 | Watusi Energy LLC | Midland, TX 79710 | Oil & Gas Operator | Apr 2026 |
| 652 | Way, Ralph L., Inc. | Midland, TX 79701 | Oil & Gas Operator | Apr 2026 |
| 653 | Westar Energy, Inc. | Midland, TX 79705 | Oil & Gas Operator | Mar 2008 |
| 654 | Westland Oil Development Corp. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2008 |
| 655 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 656 | WGR, Inc. | Houston, TX 77046 | Gas Operator | Jul 2007 |
| 657 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 658 | Wild Cat Operating Company | Victoria, TX 77903 | Oil & Gas Operator | Mar 2008 |
| 659 | Williams Oil Company | Midland, TX 79710 | Oil & Gas Operator | Apr 2026 |
| 660 | Wind River Energy, Inc. | Midland, TX 79710 | Oil & Gas Operator | Apr 2026 |
| 661 | WTG Exploration | Midland, TX 79705 | Oil & Gas Operator | Apr 2026 |
| 662 | Xeric Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Jul 1997 |
| 663 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 664 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 665 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Apr 2026 |
| 666 | Yocham Oil And Gas Company | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 667 | Zachry Oil And Gas Properties | Midland, TX 79708 | Oil & Gas Operator | Apr 2026 |
| 668 | Zachry Operating | Midland, TX 79708 | Oil & Gas Operator | Jan 2011 |
| 669 | Zarvona Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |