| 501 | Skycap Energy, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jan 2025 |
| 502 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2025 |
| 503 | Slawson, Donald C. | Wichita, KS 67202 | Oil & Gas Operator | Oct 2024 |
| 504 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | Jan 2025 |
| 505 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Mar 2025 |
| 506 | Smith Edward F | Avant, OK 74001-0024 | Oil & Gas Operator | Nov 2014 |
| 507 | Sneed William A Bill | Cleveland, OK 74020-1007 | Oil & Gas Operator | Dec 2024 |
| 508 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 509 | Sooner Acquisition Corp | Wichita, KS 67206 | Oil & Gas Operator | Sep 1993 |
| 510 | Sooner Oil & Gas | Fairview, OK 73737-1806 | Oil & Gas Operator | Jan 2025 |
| 511 | Southport Exploration Inc | Tulsa, OK 74103-4015 | Oil & Gas Operator | Nov 1998 |
| 512 | Southwest Energy LP | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 513 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Jan 2025 |
| 514 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Jan 2025 |
| 515 | St. Johns Operating #1 L.P. | Houston, TX 77060 | Oil & Gas Operator | Aug 2023 |
| 516 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 517 | Staghorn Energy, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2024 |
| 518 | Staghorn Petroleum II LLC | Tulsa, OK 74103-3500 | Oil & Gas Operator | Jan 2025 |
| 519 | Staghorn Petroleum LLC | Tulsa, OK 74103-3500 | Oil & Gas Operator | Dec 2024 |
| 520 | Stalwart Energy Co | Tulsa, OK 74103-3518 | Oil & Gas Operator | Apr 2014 |
| 521 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 2025 |
| 522 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Jan 2025 |
| 523 | Stewart K Petroleum Corp | Edmond, OK 73013 | Oil & Gas Operator | Mar 2015 |
| 524 | Stone Oak Operating LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Jan 2025 |
| 525 | Stride Energy LLC | Piedmont, OK 73078 | Oil & Gas Operator | Jan 2025 |
| 526 | Struck Rock Oil And Gas LLC | Geary, OK 73040 | Oil & Gas Operator | Dec 2024 |
| 527 | Summit Overseas Expl., Inc. | Denver, CO 80226 | Oil & Gas Operator | Apr 2007 |
| 528 | Sun Refining & Marketing | Philadelphia, PA 19103 | Oil & Gas Operator | Jul 2015 |
| 529 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Mar 2025 |
| 530 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Nov 2024 |
| 531 | Sunnybook Transmission Inc | Houston, TX 77002 | Oil & Gas Operator | Oct 1992 |
| 532 | Sunoco Partners MKT & Terminal | Tulsa, OK 74102-2039 | Oil & Gas Operator | Jan 2019 |
| 533 | Sunrise Energy Co | Dallas, TX 75206 | Oil & Gas Operator | Aug 1993 |
| 534 | Sunterra Energy Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2009 |
| 535 | Superior Midstream, LLC | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2020 |
| 536 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 537 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 538 | Tack Operating LLC | Oklahoma City, OK 73172-1492 | Oil & Gas Operator | Aug 2021 |
| 539 | Tag Team Resources LLC | Eufaula, OK 74432 | Oil & Gas Operator | Dec 2024 |
| 540 | Tamworth Resources LLC | Broken Arrow, OK 74012 | Oil & Gas Operator | Dec 2024 |
| 541 | Tapoil Inc | Elmore City, OK 73433-9077 | Oil & Gas Operator | Jul 2021 |
| 542 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Jan 2025 |
| 543 | Tbi Exploration Inc | Englewood, CO 801556525 | Oil & Gas Operator | Jun 2011 |
| 544 | Tcina Inc | Seminole, OK 74868 | Oil & Gas Operator | May 2023 |
| 545 | TD Operating Inc | Hinton, OK 73047 | Oil & Gas Operator | Jan 2025 |
| 546 | Te-Ray Resources, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Mar 2025 |
| 547 | Technical Energy Services, Inc. | Norman, OK 73070 | Oil & Gas Operator | Dec 2024 |
| 548 | Tecolote Energy Operating, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Jan 2024 |
| 549 | Tenaska Marketing Ventures | Omaha, NE 68154 | Oil & Gas Operator | Mar 2021 |
| 550 | Teocalli Exploration LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jan 2025 |
| 551 | Tepee Petroleum Company, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 2014 |
| 552 | Tex/Con Oil & Gas Company | Houston, TX 77074 | Oil & Gas Operator | Feb 2001 |
| 553 | Texaco Exploration And Production Inc | Houston, TX 77236 | Oil & Gas Operator | Nov 2024 |
| 554 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 555 | Texaco Oils, Inc. | Tulsa, OK 74102-2420 | Oil & Gas Operator | Jan 2003 |
| 556 | Texas Oil & Gas Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 557 | Texas Southwest Gas LLC | Tulsa, OK 74121 | Oil & Gas Operator | Oct 2022 |
| 558 | Texla Energy Products LLC | Houston, TX 77002 | Oil Operator | Sep 2020 |
| 559 | TGX Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2004 |
| 560 | The Warren Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Jan 2016 |
| 561 | Tide West Oil Company | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2021 |
| 562 | TLS Oil & Gas Inc | Kingfisher, OK 73750-0901 | Oil & Gas Operator | Dec 2024 |
| 563 | Toklan Oil And Gas Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2025 |
| 564 | Toklan Oil Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 565 | Torch Energy MKT Inc | Houston, TX 77010 | Oil & Gas Operator | Aug 1996 |
| 566 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 567 | Total Minatome Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 1998 |
| 568 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 569 | Trans-Western Expl. Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 1993 |
| 570 | Transok LLC | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Jul 2020 |
| 571 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Mar 2025 |
| 572 | Trigg Drilling Company Inc | Oklahoma City, OK 73105 | Oil & Gas Operator | Jan 2013 |
| 573 | Troy Energy Operating LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2024 |
| 574 | Tulsa Energy Partners LLC | Tulsa, OK 74103-4461 | Oil & Gas Operator | Jan 2025 |
| 575 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 576 | Txok Energy Resources Company | Tulsa, OK 74172-0140 | Oil & Gas Operator | Feb 2017 |
| 577 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 578 | Unbridled Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 579 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 580 | Union Texas Petroleum Corp. | Houston, TX 77252-2120 | Oil & Gas Operator | Dec 2014 |
| 581 | Unit Drilling & Exploration Co | Tulsa, OK 74132-5300 | Oil & Gas Operator | Oct 2024 |
| 582 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2025 |
| 583 | United Energy Operating, LLC | Edmond, OK 73083 | Oil & Gas Operator | Mar 2025 |
| 584 | United Oil Corporation | Denver, CO 80202-3813 | Oil & Gas Operator | Dec 2024 |
| 585 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Mar 2025 |
| 586 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Mar 2025 |
| 587 | Valero Marketing & Supply Co | San Antonio, TX 78269-6000 | Oil & Gas Operator | Sep 2023 |
| 588 | Validus Energy II Midcon LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2025 |
| 589 | Valjohn Energy Corporation | Oklahoma City, OK 73142-6090 | Oil & Gas Operator | Dec 2024 |
| 590 | Vantage Point Operating Co | Houston, TX 77057 | Oil & Gas Operator | Dec 2014 |
| 591 | Vaquero Resources, LLC | Edmond, OK 73034 | Oil & Gas Operator | Jan 2025 |
| 592 | Vastar Resources Inc | Houston, TX 77253 | Oil & Gas Operator | Nov 2024 |
| 593 | Viersen & Cochran Drilling Company | | Oil & Gas Operator | May 2015 |
| 594 | Vintage Gas Inc | Tulsa, OK 74119-1029 | Oil & Gas Operator | Jun 2007 |
| 595 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Dec 2024 |
| 596 | Wagner & Brown LP | Midland, TX 79702-1714 | Oil & Gas Operator | Aug 2022 |
| 597 | Wallace Oil & Gas Inc | Oklahoma City, OK 73156 | Oil & Gas Operator | Mar 2025 |
| 598 | Walsh Jr F Howard | Fort Worth, TX 76102-4773 | Oil & Gas Operator | Sep 2024 |
| 599 | Ward Gas Marketing Inc | Enid, OK 73702 | Oil & Gas Operator | Sep 2011 |
| 600 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Dec 2024 |