| 501 | Sundance Operating Co | | Oil & Gas Operator | Jul 2016 |
| 502 | Superior Oil & Gas LLC | Ringwood, OK 73768-9658 | Oil & Gas Operator | Mar 2026 |
| 503 | Superior Production LLC | Ringwood, OK 73768 | Oil & Gas Operator | Mar 2026 |
| 504 | Sweetwater Exploration LLC | Norman, OK 73069-5636 | Oil & Gas Operator | Mar 2026 |
| 505 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 506 | T B K Energy Company | Brenham, TX 77833 | Oil & Gas Operator | Apr 2026 |
| 507 | Tahoe Exploration Inc. | Abilene, TX 79608 | Oil & Gas Operator | Mar 2016 |
| 508 | Tallgrass Energy, L.L.C. | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2026 |
| 509 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Apr 2026 |
| 510 | TC Energy LLC | Covington, OK 73730-2116 | Oil & Gas Operator | Sep 2014 |
| 511 | Te-Ray Energy Inc | Oklahoma City, OK 73108 | Oil & Gas Operator | Mar 2026 |
| 512 | Te-Ray Resources, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Jun 2026 |
| 513 | Tessera Energy LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Mar 2026 |
| 514 | Tex-Star Production | Dallas, TX 75206 | Oil & Gas Operator | Mar 2026 |
| 515 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 516 | Texas Meridian Operating Co. Inc | Houston, TX 77079 | Oil & Gas Operator | Oct 1993 |
| 517 | Texasgulf Inc. | Newgulf, TX 77462 | Oil & Gas Operator | Jul 1994 |
| 518 | Thomas J L Engineering Inc | Edmond, OK 73003-0026 | Oil & Gas Operator | Jul 2016 |
| 519 | Thunder Oil & Gas, LLC | Ardmore, OK 73402 | Oil & Gas Operator | Apr 2026 |
| 520 | Tide West Oil Company | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2021 |
| 521 | Tilley Oil & Gas, Inc. | Oklahoma City, OK 73172 | Oil & Gas Operator | Jun 2026 |
| 522 | Tilley Oil Inc | Velma, OK 73491 | Oil & Gas Operator | Apr 2026 |
| 523 | Token Operating, LLC | Enid, OK 73703-1094 | Oil & Gas Operator | Apr 2026 |
| 524 | Toklan Oil And Gas Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2026 |
| 525 | Toklan Oil Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 526 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 527 | Trans Pacific Oil Corporation | Wichita, KS 67202 | Oil & Gas Operator | Mar 2026 |
| 528 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 529 | Trepco Production Company Inc | Yukon, OK 73099 | Oil & Gas Operator | Mar 2026 |
| 530 | Tri-Unity Inc | Sand Springs, OK 74063-4401 | Oil & Gas Operator | Jun 2009 |
| 531 | Triad Energy, Inc. | Oklahoma City, OK 73105-1401 | Oil & Gas Operator | Apr 2026 |
| 532 | Triplett Larry W | Oklahoma City, OK 73112-5325 | Oil & Gas Operator | Mar 2015 |
| 533 | Triumph Energy Inc | Lafayette, LA 70505 | Oil & Gas Operator | Nov 2015 |
| 534 | Tulsa Energy Partners LLC | Tulsa, OK 74103-4461 | Oil & Gas Operator | Mar 2026 |
| 535 | Turner Resources Inc | Hennessey, OK 73742 | Oil & Gas Operator | Mar 2026 |
| 536 | Twenty/Twenty Oil & Gas Inc | Hennessey, OK 73742 | Oil & Gas Operator | Mar 2026 |
| 537 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 538 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 539 | Unbridled Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2026 |
| 540 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Jun 2026 |
| 541 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jun 2026 |
| 542 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Jun 2026 |
| 543 | Validus Energy II Midcon LLC | Denver, CO 80202 | Oil & Gas Operator | Jun 2026 |
| 544 | Valjohn Energy Corporation | Dover, OK 73734 | Oil & Gas Operator | Mar 2026 |
| 545 | Viersen & Cochran Drilling Company | | Oil & Gas Operator | May 2015 |
| 546 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Feb 2026 |
| 547 | VRC Oil & Gas Operating Co | Oklahoma City, OK 73116-1431 | Oil & Gas Operator | Jun 2019 |
| 548 | W C S Inc | Pottsboro, TX 75076 | Oil & Gas Operator | Oct 2019 |
| 549 | W F D Oil Corp. | Edmond, OK 73012 | Oil & Gas Operator | Apr 2026 |
| 550 | Waggoner Oil & Gas Corp | Enid, OK 73703-1152 | Oil & Gas Operator | Apr 2026 |
| 551 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2026 |
| 552 | Ward Oil Company An Okla Corp | McAlester, OK 74501 | Oil & Gas Operator | Feb 1993 |
| 553 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Mar 2026 |
| 554 | Watkins J L | Henryetta, OK 74437 | Oil & Gas Operator | Apr 2026 |
| 555 | Wellco Energy Inc | Harrah, OK 73045 | Oil & Gas Operator | Apr 2026 |
| 556 | Wentworth Operating Company | Oklahoma City, OK 73162-1863 | Oil & Gas Operator | Apr 2026 |
| 557 | Western Division Investments Inc | Enid, OK 73701 | Oil & Gas Operator | Jul 2021 |
| 558 | Western Mountain Resources LLC | Cogan Station, PA 17728 | Oil & Gas Operator | Mar 2026 |
| 559 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Apr 2026 |
| 560 | White Goat Resources LLC | Yukon, OK 73099 | Oil & Gas Operator | Apr 2026 |
| 561 | White Operating Company | Oklahoma City, OK 73159-7136 | Oil & Gas Operator | Apr 2026 |
| 562 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2026 |
| 563 | Wil-MC Oil Corporation The | Irving, TX 75015-2510 | Oil & Gas Operator | Mar 1999 |
| 564 | Wildhorse Oil & Gas Corporation | Ardmore, OK 73402 | Oil & Gas Operator | May 2019 |
| 565 | Wimberley James A | Dallas, TX 75229-6180 | Oil & Gas Operator | Nov 2014 |
| 566 | Wind River Exploration Inc | Sewickley, PA 15143 | Oil & Gas Operator | Feb 2026 |
| 567 | Wise James W | Okmulgee, OK 74447 | Oil & Gas Operator | Oct 1996 |
| 568 | WLW Oil & Gas LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Apr 2026 |
| 569 | Wood Fay C Estate | Enid, OK 73703 | Oil & Gas Operator | Jun 2013 |
| 570 | Woolsey Petroleum Corporation | Wichita, KS 67202 | Oil & Gas Operator | Feb 2026 |
| 571 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jun 2026 |
| 572 | Yale Oil Association, Inc. | Oklahoma City, OK 73105 | Oil & Gas Operator | Apr 2026 |
| 573 | Young H Inc | Edmond, OK 73013 | Oil & Gas Operator | Oct 1993 |
| 574 | Zeiders Bros. Oil & Gas Company, L.L.C. | Edmond, OK 73003 | Oil & Gas Operator | Mar 2026 |