| 601 | Sanook Inc | Oklahoma City, OK 73156-0548 | Oil & Gas Operator | Jan 2007 |
| 602 | Santa Fe Minerals, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Sep 2013 |
| 603 | Scarth Oil & Gas Co | Amarillo, TX 79101 | Oil & Gas Operator | Feb 1999 |
| 604 | Schmid Properties, Inc. | Hico, TX 76457 | Oil & Gas Operator | Jun 2026 |
| 605 | Scoggins Production LLC | Enid, OK 73703-3002 | Oil & Gas Operator | Mar 2026 |
| 606 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 607 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 608 | Seagull Midcon Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 609 | Seals And Brown Oil Operating | Norman, OK 73072-3020 | Oil & Gas Operator | Sep 2024 |
| 610 | Seals Oil Company | Fox, OK 73435-0222 | Oil & Gas Operator | Nov 2011 |
| 611 | Search Drilling Company | Houston, TX 77010 | Oil & Gas Operator | Feb 2001 |
| 612 | Select Exploration Group LLC | Eufaula, OK 74432 | Oil & Gas Operator | May 2024 |
| 613 | Select Water Solutions, LLC | Gainesville, TX 76240 | Oil Operator | Feb 2026 |
| 614 | Seneca Oil Company | Tulsa, OK 74121-1518 | Oil & Gas Operator | Jan 2015 |
| 615 | Sequoyah Energy Holdings LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Mar 2026 |
| 616 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Feb 2026 |
| 617 | Shoreline Operating LLC | Oklahoma City, OK 73113 | Oil & Gas Operator | Mar 2026 |
| 618 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Jun 2026 |
| 619 | Silver Pines Energy Corp. | Houston, TX 77005 | Oil & Gas Operator | Feb 2026 |
| 620 | Simpson Oil & Land Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2026 |
| 621 | Singer Oil Co LLC | Hennessey, OK 73742 | Oil & Gas Operator | Mar 2026 |
| 622 | Skycap Energy, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jun 2026 |
| 623 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | Mar 2026 |
| 624 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Jun 2026 |
| 625 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 626 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 627 | Sooner Crude Inc | Tulsa, OK 74136-9107 | Oil & Gas Operator | Sep 2008 |
| 628 | Sorrels J R Dba Cheyenne Oil Properties | Ponca City, OK 74601 | Oil & Gas Operator | Jul 2022 |
| 629 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 630 | Southwest Energy LP | Tulsa, OK 74136 | Oil & Gas Operator | Dec 2025 |
| 631 | Southwest Exploration Company | Oklahoma City, OK 73132-2230 | Oil & Gas Operator | Jun 2017 |
| 632 | Sparks Petroleum Company | Oklahoma City, OK 73128 | Oil & Gas Operator | Mar 1998 |
| 633 | Special Energy Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Jun 2026 |
| 634 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Mar 2026 |
| 635 | St Johns Operating #1 LP | Houston, TX 77060 | Oil & Gas Operator | Aug 2023 |
| 636 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 637 | Staab Alan R | Tulsa, OK 74114-4213 | Oil & Gas Operator | Sep 2010 |
| 638 | Staghorn Energy, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2026 |
| 639 | Staghorn Petroleum II LLC | Tulsa, OK 74103-3500 | Oil & Gas Operator | Mar 2026 |
| 640 | Staghorn Petroleum LLC | Tulsa, OK 74103-3500 | Oil & Gas Operator | Feb 2026 |
| 641 | Staghorn Resources, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2015 |
| 642 | STB Energy Inc. | Tulsa, OK 74105 | Oil & Gas Operator | Jul 2008 |
| 643 | Stephen Michael Inc | Midwest City, OK 73130-5200 | Oil & Gas Operator | Oct 2015 |
| 644 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Mar 2026 |
| 645 | Stewart K Petroleum Corp | Edmond, OK 73013 | Oil & Gas Operator | Mar 2015 |
| 646 | Stone Oak Operating LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Mar 2026 |
| 647 | Summit Overseas Expl., Inc. | Lakewood, CO 80226 | Oil & Gas Operator | Apr 2007 |
| 648 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Jun 2026 |
| 649 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 650 | Sunterra Energy Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2009 |
| 651 | Superior Midstream, LLC | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2020 |
| 652 | Sweetwater Exploration LLC | Norman, OK 73069-5636 | Oil & Gas Operator | Feb 2026 |
| 653 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Apr 2026 |
| 654 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Mar 2026 |
| 655 | Tarrant Tracy Dba Trace Oil | Crescent, OK 73028 | Oil & Gas Operator | Feb 2021 |
| 656 | Tbi Exploration Inc | Englewood, CO 801556525 | Oil & Gas Operator | Jun 2011 |
| 657 | Te-Ray Resources, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Jun 2026 |
| 658 | Technical Energy Services, Inc. | Norman, OK 73070 | Oil & Gas Operator | Feb 2026 |
| 659 | Temex Energy Inc | Oklahoma City, OK 73101 | Oil & Gas Operator | Feb 2002 |
| 660 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Dec 2025 |
| 661 | Teocalli Exploration LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Mar 2026 |
| 662 | Tex-Star Production | Dallas, TX 75206 | Oil & Gas Operator | Mar 2026 |
| 663 | Texaco Exploration & Prod Inc | Houston, TX 77236 | Oil & Gas Operator | Feb 2026 |
| 664 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 665 | Texaco Oils Inc | Tulsa, OK 74102-2420 | Oil & Gas Operator | Jan 2003 |
| 666 | Texas Oil & Gas Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 667 | Thompson, Joe L., Inc. | Oklahoma City, OK 73132 | Oil & Gas Operator | Oct 2005 |
| 668 | Tide West Oil Company | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2021 |
| 669 | Tidemark Exploration | Tulsa, OK 74170 | Oil & Gas Operator | May 2005 |
| 670 | TK Drilling Corp. | Tulsa, OK 74133 | Oil & Gas Operator | Feb 2026 |
| 671 | Toklan Oil And Gas Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2026 |
| 672 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 673 | Total Minatome Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 1998 |
| 674 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 675 | Trail Ridge Energy Partners, LLC | Grapevine, TX 76051 | Oil & Gas Operator | Mar 2026 |
| 676 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Jun 2026 |
| 677 | Trenchco Inc | Shawnee, OK 74802-3577 | Oil & Gas Operator | Apr 2015 |
| 678 | Tri-Ex Petroleum, L.P. | Amarillo, TX 79101 | Oil & Gas Operator | Jan 2013 |
| 679 | Triexco Inc | Tulsa, OK 74119 | Oil & Gas Operator | Dec 2012 |
| 680 | Triplett Larry W | Oklahoma City, OK 73112-5325 | Oil & Gas Operator | Mar 2015 |
| 681 | Tripower Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2020 |
| 682 | Turnbow John R Company | Tulsa, OK 74120-2420 | Oil & Gas Operator | Aug 2006 |
| 683 | Turner Resources Inc | Hennessey, OK 73742 | Oil & Gas Operator | Feb 2026 |
| 684 | Twenty/Twenty Oil & Gas Inc | Hennessey, OK 73742 | Oil & Gas Operator | Mar 2026 |
| 685 | Twisted Resources Inc | Blanchard, OK 73010-8463 | Oil & Gas Operator | Mar 2026 |
| 686 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 687 | Txok Energy Resources Company | Tulsa, OK 74172-0140 | Oil & Gas Operator | Feb 2017 |
| 688 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 689 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 690 | Union Texas Petroleum Corp | Houston, TX 77252-2120 | Oil & Gas Operator | Dec 2014 |
| 691 | Union Valley Petroleum Corp | Enid, OK 73701 | Oil & Gas Operator | Mar 2026 |
| 692 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Jun 2026 |
| 693 | United Production Company LLC | Edmond, OK 73003 | Oil & Gas Operator | Mar 2026 |
| 694 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jun 2026 |
| 695 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Jun 2026 |
| 696 | Validus Energy II Midcon LLC | Denver, CO 80202 | Oil & Gas Operator | Jun 2026 |
| 697 | Valpoint Operating, LLC | Amarillo, TX 79101 | Oil & Gas Operator | Jun 2026 |
| 698 | Van Horn Oil Company | Ada, OK 74820 | Oil & Gas Operator | Oct 1999 |
| 699 | Vantage Point Operating Co. | Houston, TX 77057 | Oil & Gas Operator | Dec 2014 |
| 700 | Vaquero Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2026 |