| 601 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 602 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2026 |
| 603 | Southwest-Operating | Penwell, TX 79776 | Oil & Gas Operator | Sep 2026 |
| 604 | Space Production Inc. | Monahans, TX 79756 | Oil & Gas Operator | Sep 2026 |
| 605 | Spenergy Corp. | Midland, TX 79701 | Oil & Gas Operator | Dec 1999 |
| 606 | Spindletop Drilling Co. | Dallas, TX 75230 | Oil & Gas Operator | Sep 2026 |
| 607 | Spiral Energy Corp. | Midland, TX 79705 | Oil & Gas Operator | Dec 2019 |
| 608 | SSC, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Sep 2026 |
| 609 | Staley Operating Co. | Midland, TX 79702 | Oil & Gas Operator | Jan 2022 |
| 610 | Stanolind Operating Corp. | Midland, TX 79701 | Oil & Gas Operator | Apr 2008 |
| 611 | Stanolind Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Apr 2021 |
| 612 | Starrak Operating Company, Inc. | Midland, TX 79706 | Oil & Gas Operator | Jun 1999 |
| 613 | STB Energy Inc. | Tulsa, OK 74105 | Oil & Gas Operator | Jul 2008 |
| 614 | Stephens, Autry C. | Midland, TX 79701 | Oil & Gas Operator | Mar 2023 |
| 615 | Stevens & Tull, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2000 |
| 616 | Steward Energy, LLC | Frisco, TX 75034 | Oil & Gas Operator | Nov 2014 |
| 617 | Stivers Inc | Graham, TX 76450 | Oil & Gas Operator | May 2003 |
| 618 | Stivers Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Feb 1995 |
| 619 | Stout Energy Inc. | Midland, TX 79708 | Oil & Gas Operator | Sep 2026 |
| 620 | Stratco Operating Co., Inc. | Austin, TX 78701 | Oil & Gas Operator | Sep 2026 |
| 621 | Stronghold Energy II Oper, LLC | Midland, TX 79702 | Oil & Gas Operator | Aug 2022 |
| 622 | Success Oil Company, Inc. | Beverly Hills, CA 90211 | Oil & Gas Operator | Sep 2026 |
| 623 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Sep 2026 |
| 624 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 625 | Synergex Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Jun 2026 |
| 626 | T & D Oil | Wichita Falls, TX 76307 | Oil & Gas Operator | Sep 2026 |
| 627 | T.G.B., Inc. | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 628 | Tap Rock Operating, LLC | Denver, CO 80203 | Oil & Gas Operator | Sep 2026 |
| 629 | Targa Midstream Services LLC | Tulsa, OK 74103 | Oil Operator | Mar 2023 |
| 630 | Taurus Exploration U.S.A., Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 1998 |
| 631 | Taylor, Ben J. Inc. | Fort Worth, TX 76185 | Oil & Gas Operator | Feb 2022 |
| 632 | Taylor, J. S. Inc. | Lewisville, TX 75057 | Oil & Gas Operator | Sep 2026 |
| 633 | Taylor-Link Operating Co. | Midland, TX 79702 | Oil & Gas Operator | Apr 2017 |
| 634 | TD Natural Resources LLC | Cuero, TX 77954 | Oil & Gas Operator | Sep 2026 |
| 635 | Teke Production LLC | Houston, TX 77269 | Oil Operator | Sep 2026 |
| 636 | Terrace Petroleum Corporation | Midland, TX 79701 | Oil & Gas Operator | Jul 2013 |
| 637 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Sep 2026 |
| 638 | Texas Consolidated Pet. Corp. | Fort Worth, TX 76109 | Oil & Gas Operator | Sep 2026 |
| 639 | Texland Petroleum Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2003 |
| 640 | Texland Petroleum, L.P. | Fort Worth, TX 76107 | Oil & Gas Operator | Sep 2026 |
| 641 | Texland-Rector & Schumacher | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2000 |
| 642 | Texon Oil Company, Inc. | Midland, TX 79710 | Oil & Gas Operator | Apr 2023 |
| 643 | Three Rivers Operating Co LLC | Austin, TX 78735 | Oil & Gas Operator | Mar 2017 |
| 644 | Three-B Oil Company, The | Monahans, TX 79756 | Oil & Gas Operator | Sep 2026 |
| 645 | Thunderbird Drilling, Inc. | Wichita, KS 67207 | Oil Operator | Oct 2008 |
| 646 | Tiburon Oil & Gas, Inc. | Midland, TX 79701 | Oil & Gas Operator | Aug 2000 |
| 647 | Tidwell Production Company | Sonora, TX 76950 | Oil & Gas Operator | Sep 2026 |
| 648 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 649 | Titus Oil & Gas Production, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2022 |
| 650 | Torch Energy Services, Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2011 |
| 651 | TPC Exploration, LLC | May, TX 76857 | Oil & Gas Operator | Sep 2026 |
| 652 | Trans-Tex Operating LLC | Dallas, TX 75367 | Oil & Gas Operator | Sep 2026 |
| 653 | Treadaway Oil Co. | Balmorhea, TX 79718 | Oil & Gas Operator | Sep 2026 |
| 654 | Triple "N" Services, Inc. | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 655 | TRP Operating LLC | Houston, TX 77024 | Oil & Gas Operator | Sep 2026 |
| 656 | TS Oil, LLC | River Oaks, TX 76114 | Oil & Gas Operator | Sep 2026 |
| 657 | Two Black Bears Oil, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2003 |
| 658 | Two P Partners, LLC | Houston, TX 77056 | Oil & Gas Operator | Sep 2026 |
| 659 | TX Heat Of The Permian Basin Inc | Odessa, TX 79768 | Oil & Gas Operator | Dec 2021 |
| 660 | U. S. Energy Development Corporation | Fort Worth, TX 76164 | Oil & Gas Operator | Sep 2026 |
| 661 | U. S. Operating, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Jul 2025 |
| 662 | Ultra Petroleum (U.S.A.), Inc. | Granbury, TX 76048 | Oil & Gas Operator | Sep 2003 |
| 663 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 664 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 665 | United Energy Corporation | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2026 |
| 666 | United Oil & Minerals L. P. | Austin, TX 78746 | Oil & Gas Operator | Jun 2003 |
| 667 | United Oil & Minerals, Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2001 |
| 668 | United Oil & Shale LLC | Woodward, OK 73801 | Oil & Gas Operator | Sep 2026 |
| 669 | United Resources LP | Austin, TX 78746 | Oil & Gas Operator | Oct 2011 |
| 670 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 671 | Upp Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2026 |
| 672 | Valley Gathering Company | Midland, TX 79702 | Oil & Gas Operator | Feb 1997 |
| 673 | Vanguard Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Jan 2021 |
| 674 | Vanguard Permian, LLC | Houston, TX 77057 | Oil & Gas Operator | Nov 2018 |
| 675 | Vaquero Operating | FT Stockton, TX 79735 | Oil & Gas Operator | Sep 2026 |
| 676 | Ventex Operating Corp. | Addison, TX 75001 | Oil & Gas Operator | Sep 2026 |
| 677 | Victorian Oil & Gas | Monahans, TX 79756 | Oil Operator | Sep 2026 |
| 678 | Vidonia Oil LLC | Plymouth MTNG, PA 19462 | Oil Operator | Sep 2026 |
| 679 | Viola Production Inc | Dallas, TX 75251 | Oil & Gas Operator | Sep 2026 |
| 680 | Vista Resources, Inc. (A) | Midland, TX 79701 | Oil & Gas Operator | Feb 2000 |
| 681 | Vital Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Sep 2026 |
| 682 | Vogel, A. J., Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 1994 |
| 683 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2026 |
| 684 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 685 | Walbet | Monahans, TX 79756 | Oil & Gas Operator | Dec 1993 |
| 686 | Walbet, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Sep 2026 |
| 687 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Sep 2026 |
| 688 | Walton Properties LTD. | Midland, TX 79702 | Oil & Gas Operator | Feb 2004 |
| 689 | Ward, Ted G. Jr. | Monahans, TX 79756 | Oil & Gas Operator | Nov 2000 |
| 690 | Waterbridge Texas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Sep 2026 |
| 691 | Watson Packer Employee Fund | Monahans, TX 79756 | Oil & Gas Operator | Sep 2026 |
| 692 | Way, Ralph L., Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 693 | Wellstar Corporation | Northglenn, CO 80233 | Oil & Gas Operator | Jul 2026 |
| 694 | Western Disposal Systems, Inc. | Corrales, NM 87048 | Oil Operator | Sep 2026 |
| 695 | Western Reserves Oil Co Inc | Midland, TX 79705 | Oil & Gas Operator | Oct 2020 |
| 696 | Westover Production Co., LLC | Kermit, TX 79745 | Oil & Gas Operator | Sep 2026 |
| 697 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 698 | White Sail Resources LLC | Austin, TX 78731 | Oil Operator | Sep 2026 |
| 699 | White Wing Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2012 |
| 700 | White, Cecil | Monahans, TX 79756 | Oil & Gas Operator | Mar 2017 |