| 401 | Regency Exploration Inc | Oklahoma City, OK 73102-5605 | Oil & Gas Operator | Mar 1999 |
| 402 | Research Oil Company Inc | Norman, OK 73070-8776 | Oil & Gas Operator | Aug 2019 |
| 403 | Resources Investment Corp | Denver, CO 80202 | Oil & Gas Operator | May 2023 |
| 404 | Revelation Resources | Cypress, TX 77410-2578 | Oil & Gas Operator | Jan 2024 |
| 405 | Richland Resources Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Apr 2024 |
| 406 | Ricks Exploration Co | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 407 | Riviera Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2024 |
| 408 | Rja Energy LLC | | Oil & Gas Operator | Mar 2024 |
| 409 | Roberson Oil Company | Houston, TX 77046 | Oil & Gas Operator | Jan 2024 |
| 410 | Robson Petroleum Company | Tulsa, OK 74104 | Oil & Gas Operator | Jan 1995 |
| 411 | Rockwell Energy Corporation | Tulsa, OK 74105 | Oil & Gas Operator | Apr 2014 |
| 412 | Roka Management Inc | | Oil & Gas Operator | Jan 2024 |
| 413 | Royal Oaks Petroleum Corp | Fort Worth, TX 76116 | Oil & Gas Operator | Dec 2001 |
| 414 | Royalty Energy Development LLC | Edmond, OK 73083 | Oil & Gas Operator | Feb 2024 |
| 415 | Russell D Meloy Oil & Gas Co | Enid, OK 73703-1623 | Oil & Gas Operator | Feb 2024 |
| 416 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 417 | S & M Production Inc | Pawnee, OK 74058-4516 | Oil & Gas Operator | Aug 2023 |
| 418 | S/H Petroleum Corporation | Hennessey, OK 73742-0477 | Oil & Gas Operator | Feb 2016 |
| 419 | Salty Dog Disposal LLC | | Oil Operator | Mar 2024 |
| 420 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 421 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 422 | Sand Resources LLC | Norman, OK 73072-4805 | Oil & Gas Operator | Aug 2012 |
| 423 | Sandy Petroleum Inc | Shawnee, OK 74801-5634 | Oil & Gas Operator | Jan 2024 |
| 424 | Sanook Inc | Oklahoma City, OK 73156-0548 | Oil & Gas Operator | Jan 2007 |
| 425 | Santa Fe Energy Company | Midland, TX 79701 | Oil & Gas Operator | Dec 2015 |
| 426 | Santa Fe Energy Operating Partner LP | Midland, TX 79701 | Oil & Gas Operator | Sep 2004 |
| 427 | Scout Energy Corporation | Edmond, OK 73083-1348 | Oil & Gas Operator | Feb 2024 |
| 428 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 429 | Seagull Operating Co., Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Feb 2024 |
| 430 | Seahawk Oil International Inc | Newport Beach, CA 92660 | Oil & Gas Operator | Oct 1997 |
| 431 | Sec Production Inc | Edmond, OK 73013-3709 | Oil & Gas Operator | Feb 2024 |
| 432 | Senax Inc | Tulsa, OK 74105-2206 | Oil & Gas Operator | Jan 2024 |
| 433 | Shamrock Well Operations LLC | | Oil & Gas Operator | Feb 2024 |
| 434 | Sharber Billy Jack Operating | Konawa, OK 74849-0071 | Oil & Gas Operator | Mar 2015 |
| 435 | Shawver & Son Inc | Oklahoma City, OK 73154-0778 | Oil & Gas Operator | Dec 2023 |
| 436 | Shields Energy Inc | Fort Smith, AR 72901-4607 | Oil & Gas Operator | Jan 2024 |
| 437 | Shields Operating Inc | Fort Smith, AR 72901-3834 | Oil & Gas Operator | Oct 2021 |
| 438 | Signature Exploration Inc. | Shawnee, OK 74804-4130 | Oil & Gas Operator | Mar 2015 |
| 439 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Apr 2024 |
| 440 | Silver Pines Energy Corp. | Houston, TX 77005 | Oil & Gas Operator | Feb 2024 |
| 441 | Singer Fleischaker Oil Op. Co. | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2002 |
| 442 | Sju Holdings LLC | | Oil & Gas Operator | Jan 2024 |
| 443 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Apr 2024 |
| 444 | SNR Central Oklahoma Operating LLC | | Oil Operator | Feb 2024 |
| 445 | SNR Operating, LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Apr 2024 |
| 446 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 447 | Sooner Drilling Inc | Shawnee, OK 74802-0037 | Oil & Gas Operator | Jan 2005 |
| 448 | Southcreek Petroleum Co LLC | | Oil & Gas Operator | Oct 2023 |
| 449 | Southern Mineral Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2001 |
| 450 | Southern Resources Inc | Oklahoma City, OK 73118-4821 | Oil & Gas Operator | Feb 2024 |
| 451 | Southwest Exploration Company | Oklahoma City, OK 73132-2230 | Oil & Gas Operator | Jun 2017 |
| 452 | SP Energy Development Company | Seattle, WA 98101-3277 | Oil & Gas Operator | Mar 2015 |
| 453 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Jan 2024 |
| 454 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Feb 2024 |
| 455 | Spring Operating Company | Edmond, OK 73083-2048 | Oil & Gas Operator | Feb 2024 |
| 456 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 457 | Stark Oil Properties | Asher, OK 74826 | Oil & Gas Operator | Jan 1997 |
| 458 | Statex Petroleum Inc | Dallas, TX 75229 | Oil & Gas Operator | Dec 2000 |
| 459 | Stauros Operating Company | Edmond, OK 73083-2707 | Oil & Gas Operator | Mar 2001 |
| 460 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2024 |
| 461 | Stetson Energy Corporation | Duncan, OK 73534-0098 | Oil & Gas Operator | Mar 2015 |
| 462 | Strat Land Exploration Company | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2024 |
| 463 | Streamline Oil And Gas Inc | Alex, OK 73002-0117 | Oil & Gas Operator | Mar 2024 |
| 464 | Sullivant G W | Oklahoma City, OK 73172-1135 | Oil & Gas Operator | Aug 2001 |
| 465 | Sun Refining & Marketing | Philadelphia, PA 19103 | Oil & Gas Operator | Jul 2015 |
| 466 | Sunoco Partners MKT & Terminal | Tulsa, OK 74102-2039 | Oil & Gas Operator | Jan 2019 |
| 467 | Sunterra Energy Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2009 |
| 468 | Superior Saltwater Disposal LLC | | Oil & Gas Operator | Dec 2016 |
| 469 | Swadley Et Al | Holdenville, OK 74848-0794 | Oil & Gas Operator | Nov 2014 |
| 470 | Sweetwater Exploration LLC | Norman, OK 73069-5636 | Oil & Gas Operator | Jan 2024 |
| 471 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 472 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 473 | T & S Mud Disposal LLC | Lindsay, OK 73052-0754 | Oil Operator | Mar 2013 |
| 474 | T C Craighead & Company LLC | Ardmore, OK 73402-0576 | Oil & Gas Operator | Aug 2019 |
| 475 | Tat, Inc. | Oklahoma City, OK 73127 | Oil & Gas Operator | Feb 2023 |
| 476 | Taylor R C Companies Inc | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | May 2021 |
| 477 | Te-Ray Resources, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Apr 2024 |
| 478 | Tema Oil Company | Amarillo, TX 79101 | Oil & Gas Operator | Jun 2009 |
| 479 | Terra Production Company | Okemah, OK 74859-5924 | Oil & Gas Operator | Apr 2020 |
| 480 | Texas American Oil Corporation | Midland, TX 79701 | Oil & Gas Operator | Jan 2001 |
| 481 | The Quintin Little Company Inc | Ardmore, OK 73402-1509 | Oil & Gas Operator | Feb 2024 |
| 482 | Thomas J L Engineering Inc | Edmond, OK 73003-0026 | Oil & Gas Operator | Jul 2016 |
| 483 | Thomas, R. W. Inc. | Norman, OK 73070 | Oil & Gas Operator | Apr 2015 |
| 484 | Tidemark Exploration | Tulsa, OK 74170 | Oil & Gas Operator | May 2005 |
| 485 | Tiger Trucks Inc | Seminole, OK 74868 | Oil & Gas Operator | Feb 2024 |
| 486 | Toklan Oil And Gas Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Feb 2024 |
| 487 | Toklan Oil Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 488 | Tonys Crude Oil Reclaiming Plant Inc | | Oil Operator | Jan 2024 |
| 489 | Trail Ridge Energy Partners, LLC | Grapevine, TX 76051 | Oil & Gas Operator | Feb 2024 |
| 490 | Transoil, Inc. | Oklahoma City, OK 73129 | Oil & Gas Operator | Apr 2024 |
| 491 | Trey Resources Inc. | Midland, TX 79710 | Oil & Gas Operator | Jan 2024 |
| 492 | Trigg Drilling Company Inc | Oklahoma City, OK 73105 | Oil & Gas Operator | Jan 2013 |
| 493 | Trinity Resources, Inc. | Houston, TX 77277 | Oil & Gas Operator | May 2020 |
| 494 | Triple C Properties Inc | Seminole, OK 74818-0481 | Oil & Gas Operator | Jun 2023 |
| 495 | Tripower Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2020 |
| 496 | Trout Disposal Well Inc | Hammon, OK 73650-0292 | Oil & Gas Operator | Jul 2016 |
| 497 | TRP-Ok Properties LLC | | Oil & Gas Operator | Feb 2024 |
| 498 | Twenty/Twenty Oil & Gas Inc | Hennessey, OK 73742-0247 | Oil & Gas Operator | Feb 2024 |
| 499 | Twisted Resources Inc | | Oil & Gas Operator | Feb 2024 |
| 500 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |