| 501 | Simmons Donald M | Muskogee, OK 74401 | Oil & Gas Operator | May 2013 |
| 502 | Singer Oil Co LLC | Hennessey, OK 73742 | Oil & Gas Operator | Feb 2025 |
| 503 | Singer Oil Company | Oklahoma City, OK 73148 | Oil & Gas Operator | Jan 2025 |
| 504 | Skycap Energy, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2025 |
| 505 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2025 |
| 506 | Slawson, Donald C. | Wichita, KS 67202 | Oil & Gas Operator | Oct 2024 |
| 507 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | Feb 2025 |
| 508 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Apr 2025 |
| 509 | Smith Edward F | Avant, OK 74001-0024 | Oil & Gas Operator | Nov 2014 |
| 510 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 511 | Sooner Exploration & Development Co Inc | Enid, OK 73702-3525 | Oil & Gas Operator | Oct 2023 |
| 512 | Sooner Oil & Gas | Fairview, OK 73737-1806 | Oil & Gas Operator | Jan 2025 |
| 513 | Sorrels J R Dba Cheyenne Oil Properties | Ponca City, OK 74601 | Oil & Gas Operator | Jul 2022 |
| 514 | Southern Management Inc | Camargo, OK 73835 | Oil Operator | Jun 1992 |
| 515 | Southwest Energy LP | Houston, TX 77002 | Oil & Gas Operator | Jan 2025 |
| 516 | SP Energy Development Company | Seattle, WA 98101-3277 | Oil & Gas Operator | Mar 2015 |
| 517 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Feb 2025 |
| 518 | Special Energy Corporation | Stillwater, OK 74076 | Oil & Gas Operator | Apr 2025 |
| 519 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Feb 2025 |
| 520 | Spring Operating Company | Edmond, OK 73034 | Oil & Gas Operator | Feb 2025 |
| 521 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 522 | Stalwart Energy Co | Tulsa, OK 74103-3518 | Oil & Gas Operator | Apr 2014 |
| 523 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Feb 2025 |
| 524 | Stewart K Petroleum Corp | Edmond, OK 73013 | Oil & Gas Operator | Mar 2015 |
| 525 | Stoneriver Energy, LLC | Lubbock, TX 79424 | Oil & Gas Operator | Apr 2025 |
| 526 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Apr 2025 |
| 527 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Dec 2024 |
| 528 | Sunoco Partners MKT & Terminal | Tulsa, OK 74102-2039 | Oil & Gas Operator | Jan 2019 |
| 529 | Sweetwater Exploration LLC | Norman, OK 73069-5636 | Oil & Gas Operator | Jan 2025 |
| 530 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 531 | T & S Mud Disposal LLC | Lindsay, OK 73052-0754 | Oil Operator | Mar 2013 |
| 532 | T-K Exploration Company | Oklahoma City, OK 73102-7029 | Oil & Gas Operator | Mar 2015 |
| 533 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Apr 2025 |
| 534 | Tack Operating LLC | Oklahoma City, OK 73172-1492 | Oil & Gas Operator | Aug 2021 |
| 535 | Tahoe Exploration Inc. | Abilene, TX 79608 | Oil & Gas Operator | Mar 2016 |
| 536 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Feb 2025 |
| 537 | Taylor John A | | Oil & Gas Operator | Jan 2016 |
| 538 | Tecolote Energy Operating, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Jan 2024 |
| 539 | Temex Energy, Inc. | Oklahoma City, OK 73101 | Oil & Gas Operator | Feb 2002 |
| 540 | Templar Operating LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Jan 2025 |
| 541 | Tenaska Marketing Ventures | Omaha, NE 68154 | Oil & Gas Operator | Mar 2021 |
| 542 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Dec 2024 |
| 543 | Teocalli Exploration LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2025 |
| 544 | Tepee Petroleum Company, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 2014 |
| 545 | Tex/Con Oil & Gas Company | Houston, TX 77074 | Oil & Gas Operator | Feb 2001 |
| 546 | Texaco Expl. And Prod. Inc. | Houston, TX 77236 | Oil & Gas Operator | Feb 2025 |
| 547 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 548 | Texas Oil & Gas Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 549 | Texas Southwest Gas LLC | Tulsa, OK 74121 | Oil & Gas Operator | Oct 2022 |
| 550 | Texla Energy Products LLC | Houston, TX 77002 | Oil Operator | Sep 2020 |
| 551 | TGX Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2004 |
| 552 | The William R Earnhardt Company | Bristow, OK 74010 | Oil & Gas Operator | Jan 2025 |
| 553 | Toklan Oil And Gas Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Feb 2025 |
| 554 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 555 | Total Minatome Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 1998 |
| 556 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 557 | Trail Ridge Energy Partners, LLC | Grapevine, TX 76051 | Oil & Gas Operator | Feb 2025 |
| 558 | Transok LLC | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Jul 2020 |
| 559 | Trend Gas & Oil Inc | Jenks, OK 74037 | Oil & Gas Operator | Dec 2000 |
| 560 | Trenon Oil & Gas Inc | Oklahoma City, OK 73112-4279 | Oil & Gas Operator | Sep 1996 |
| 561 | Triad Energy, Inc. | Oklahoma City, OK 73105-1401 | Oil & Gas Operator | Feb 2025 |
| 562 | Trigg Drilling Company Inc | Oklahoma City, OK 73105 | Oil & Gas Operator | Jan 2013 |
| 563 | Tripower Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2020 |
| 564 | Trout Disposal Well Inc | Hammon, OK 73650 | Oil & Gas Operator | Jul 2016 |
| 565 | Tulsa Energy Partners LLC | Tulsa, OK 74103-4461 | Oil & Gas Operator | Feb 2025 |
| 566 | Turner Resources Inc | Hennessey, OK 73742 | Oil & Gas Operator | Jan 2025 |
| 567 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 568 | Txok Energy Resources Company | Tulsa, OK 74172-0140 | Oil & Gas Operator | Feb 2017 |
| 569 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 570 | Unbridled Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 571 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 572 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2025 |
| 573 | Upland Operating, LLC | Dallas, TX 75226 | Oil & Gas Operator | Apr 2025 |
| 574 | Upland Resources, Inc. | Canadian, TX 79014 | Oil & Gas Operator | Dec 2009 |
| 575 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Apr 2025 |
| 576 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Apr 2025 |
| 577 | Valero Marketing & Supply Co | San Antonio, TX 78269-6000 | Oil & Gas Operator | Sep 2023 |
| 578 | Valpoint Operating, LLC | Amarillo, TX 79101 | Oil & Gas Operator | Apr 2025 |
| 579 | Vastar Resources Inc | Houston, TX 77253 | Oil & Gas Operator | Dec 2024 |
| 580 | Viersen & Cochran Drilling Company | | Oil & Gas Operator | May 2015 |
| 581 | Vintage Gas Inc | Tulsa, OK 74119-1029 | Oil & Gas Operator | Jun 2007 |
| 582 | Vintage Marketing Inc | Tulsa, OK 74172 | Oil & Gas Operator | Apr 2003 |
| 583 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Jan 2025 |
| 584 | Vintage Pipeline Inc | Tulsa, OK 74119-1029 | Oil & Gas Operator | Sep 2004 |
| 585 | Vitruvian II Woodford LLC | The Woodlands, TX 77381-5259 | Oil & Gas Operator | May 2019 |
| 586 | Wagner & Brown | Midland, TX 79702 | Oil & Gas Operator | Aug 2014 |
| 587 | Wagner & Brown LP | Midland, TX 79702-1714 | Oil & Gas Operator | Aug 2022 |
| 588 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2025 |
| 589 | Wagon Wheel Production Company | Crawford, OK 73638-9502 | Oil & Gas Operator | Jan 2022 |
| 590 | Walsh Jr F Howard | Fort Worth, TX 76102-4773 | Oil & Gas Operator | Jan 2025 |
| 591 | Walsh Jr F Howard Opr Co Inc | Fort Worth, TX 76102-4773 | Oil & Gas Operator | Feb 2016 |
| 592 | Walters Oil Well Service Inc | Walters, OK 73572-0467 | Oil & Gas Operator | Nov 2000 |
| 593 | Ward Gas Marketing Inc | Enid, OK 73702 | Oil & Gas Operator | Sep 2011 |
| 594 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Jan 2025 |
| 595 | Warren American Oil Company LLC | Tulsa, OK 74147 | Oil & Gas Operator | Apr 2025 |
| 596 | Washita Oil And Gas, L.L.C. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 597 | Weatherly Oil & Gas, LLC | Dallas, TX 75206 | Oil & Gas Operator | Apr 2025 |
| 598 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Feb 2025 |
| 599 | Wheeler Midstream LLC | Houston, TX 77002 | Oil & Gas Operator | May 2018 |
| 600 | Wheeler Richard Jr | Oklahoma City, OK 73112-8857 | Oil & Gas Operator | Mar 2005 |