| 401 | Samson Natural Gas Co | | Oil & Gas Operator | Oct 1992 |
| 402 | Samson Natural Gas Co And Miller Energy Miller Oil | | Oil & Gas Operator | Aug 2000 |
| 403 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 404 | Sappington Carol J | | Oil Operator | Mar 2017 |
| 405 | Sappington Crude Oil Inc | | Oil & Gas Operator | Dec 2024 |
| 406 | Sappington Henry | | Oil Operator | Dec 2010 |
| 407 | Sappington Walter B | | Oil Operator | Dec 2025 |
| 408 | Sappington Walter B Dianne M | | Oil Operator | Dec 2025 |
| 409 | Savoy Energy LP | Traverse City, MI 49685-1560 | Oil & Gas Operator | Dec 2025 |
| 410 | Savoy Exploration Inc | | Oil & Gas Operator | Feb 2020 |
| 411 | Scandia Energy Co Inc | Traverse City, MI 49684 | Oil & Gas Operator | Dec 1993 |
| 412 | Schmude And Pangborn Associates | | Oil & Gas Operator | Apr 1993 |
| 413 | Schmude Oil Co | | Oil & Gas Operator | Mar 2014 |
| 414 | Schmude Oil Inc | | Oil & Gas Operator | Dec 2025 |
| 415 | Schnell Louis L | | Oil Operator | Dec 2018 |
| 416 | Scott Don Drilling Co Inc | | Gas Operator | Oct 2000 |
| 417 | Shell Onshore Ventures Inc | Houston, TX 77210 | Gas Operator | Jun 2002 |
| 418 | Sherred Homer G And Fleeharty Willie W | | Oil & Gas Operator | Jun 1991 |
| 419 | Silver Petroleum Inc | | Gas Operator | Dec 2001 |
| 420 | Slow Stroke Productions LLC | | Oil Operator | Jan 2026 |
| 421 | Smith Petroleum Company | Spring, TX 77389 | Oil & Gas Operator | Mar 2026 |
| 422 | Sogc, Inc. | Salt Lake Cty, UT 84131 | Oil & Gas Operator | Jan 2026 |
| 423 | Somoco Inc | | Oil & Gas Operator | Dec 2025 |
| 424 | South Romeo Gas Storage Company LLC | | Gas Operator | Feb 1994 |
| 425 | Southern Energy Operating Co Inc | | Oil Operator | Oct 2025 |
| 426 | St Cleric Resources LLC | | Gas Operator | Dec 2025 |
| 427 | Staton Petroleum Inc | | Oil & Gas Operator | Dec 1994 |
| 428 | Stephens Energy Company LLC | | Oil & Gas Operator | Feb 2010 |
| 429 | Sterling Operators Inc | | Oil Operator | Dec 2025 |
| 430 | Stevenson Oil Co | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 431 | Stoney Creek Production LLC | | Oil Operator | Jan 2026 |
| 432 | Stoney Lake Production Co LLC | | Oil Operator | Dec 2025 |
| 433 | Stover Petroleum Inc | | Oil & Gas Operator | Mar 1990 |
| 434 | Sturgeon Point Development Co | | Gas Operator | Jun 2019 |
| 435 | Sullivan & Co. | Tulsa, OK 74114 | Oil & Gas Operator | May 2022 |
| 436 | Summit Essexville Inc | | Oil Operator | Dec 2014 |
| 437 | Summit Petroleum Corp And Muskegon Development C | | Oil Operator | Dec 2006 |
| 438 | Summit Petroleum Corp Of MT Pleasant | | Oil & Gas Operator | Dec 2007 |
| 439 | Summit Reed City Inc | | Oil Operator | Dec 2014 |
| 440 | Sumner Energy Inc | | Oil & Gas Operator | Dec 2025 |
| 441 | Sun Exploration And Production Co | | Oil & Gas Operator | Jan 1990 |
| 442 | Sun Oil Company | Dallas, TX 75373 | Oil & Gas Operator | Dec 2021 |
| 443 | Swepi LP | Houston, TX 77079 | Oil & Gas Operator | Jul 2020 |
| 444 | Swepi LP And Miller Brothers | | Oil & Gas Operator | Oct 1992 |
| 445 | Synergy Development Corp | | Oil Operator | Apr 2011 |
| 446 | T I Energy Services Inc | | Oil & Gas Operator | Dec 2003 |
| 447 | T X P Inc Formerly Petrotech Inc | | Oil & Gas Operator | Jul 1992 |
| 448 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Mar 2026 |
| 449 | Tai Inc Dba Trendwell Antrim Inc | | Gas Operator | Dec 2025 |
| 450 | Tallman Industries Inc | | Oil Operator | Dec 2025 |
| 451 | Tallman Trust Co | | Oil Operator | Dec 2025 |
| 452 | Tenexco Inc | Oakbrook Terrace, IL 60181 | Gas Operator | Dec 1998 |
| 453 | Terra Energy Co LLC | | Oil & Gas Operator | Apr 2018 |
| 454 | Terra Energy LTD | | Oil & Gas Operator | Apr 2018 |
| 455 | Terrel Production Co | | Oil & Gas Operator | Sep 2025 |
| 456 | Three Star Energy Inc | | Gas Operator | Nov 1997 |
| 457 | Tiger Development LLC | | Oil & Gas Operator | Aug 2019 |
| 458 | Tluczek Operating Corporation LLC | | Oil Operator | Dec 2025 |
| 459 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Mar 2026 |
| 460 | Tolas Oil And Gas Exploration Co | | Oil Operator | Dec 2025 |
| 461 | Tongue Schuster And Associates Inc | | Oil & Gas Operator | Feb 2007 |
| 462 | Total Petroleum Inc | Houston, TX 77210 | Oil & Gas Operator | Feb 1998 |
| 463 | Trahan Petroleum Inc | | Oil Operator | Jan 2026 |
| 464 | Traverse Oil Co | | Oil & Gas Operator | Nov 1983 |
| 465 | Traverse Oil Co And Federal Oil Co | | Oil & Gas Operator | Nov 1983 |
| 466 | Trendwell Energy Corporation | | Oil & Gas Operator | Oct 2025 |
| 467 | Trinity Exploration Co | | Oil Operator | Dec 1998 |
| 468 | Trolz Glynn And Associates Inc | | Oil & Gas Operator | Apr 1995 |
| 469 | Turner Petroleum Corp And Patrick Petroleum Corp | | Oil & Gas Operator | Mar 1991 |
| 470 | Tuscola Energy Inc | | Oil & Gas Operator | Dec 2025 |
| 471 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 472 | United Security Associates Inc | | Oil & Gas Operator | Dec 2020 |
| 473 | Untener Bishop Kenneth (Diocese Of Saginaw) | | Oil Operator | Dec 2024 |
| 474 | Uptex Operating Inc. | Dallas, TX 75201 | Oil & Gas Operator | May 2011 |
| 475 | V C P Michigan, LLC | | Oil & Gas Operator | Dec 2025 |
| 476 | Vanbelois Russell Inc | | Oil & Gas Operator | Apr 2000 |
| 477 | Venture Oil & Gas Inc. | Laurel, MS 39440 | Oil & Gas Operator | Dec 2025 |
| 478 | Venus Exploration, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2013 |
| 479 | Versluis A James And David And Phillip P And War | | Oil Operator | Dec 2024 |
| 480 | Victory Energy Partners LLC | | Oil & Gas Operator | Nov 2003 |
| 481 | Vonk Oil And Gas LLC | | Oil Operator | Nov 2025 |
| 482 | W 10 Holdings Inc | | Oil & Gas Operator | Dec 1998 |
| 483 | W B Osborn Oil And Gas Operations LTD | | Oil Operator | Dec 2025 |
| 484 | W W Energy Corp | | Oil & Gas Operator | Nov 2025 |
| 485 | W W Energy Corp And Flynn Energy | | Oil & Gas Operator | Oct 2024 |
| 486 | Wadi Petroleum Inc | Houston, TX 77014 | Oil & Gas Operator | May 2018 |
| 487 | Wagner And Brown LTD Dba Wagner And Brown LTD | | Oil & Gas Operator | Sep 2002 |
| 488 | Wagner Gas And Oil LLC | | Oil Operator | Jan 2026 |
| 489 | Wagner Oil And Gas | | Oil & Gas Operator | Dec 2016 |
| 490 | Wainoco Oil & Gas Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2005 |
| 491 | Ward M Haggard Oil And Gas Exploration Inc | | Oil Operator | Jan 2026 |
| 492 | Ward Williston Drilling Co | | Oil & Gas Operator | Dec 1994 |
| 493 | Weitzman Irvin | | Oil & Gas Operator | Sep 1988 |
| 494 | Well Management Services Inc | | Oil & Gas Operator | Dec 2001 |
| 495 | Wellmaster Production Co LLC | | Oil & Gas Operator | Jul 2015 |
| 496 | West Bay Exploration Company | Muenster, TX 76252 | Oil & Gas Operator | Dec 2025 |
| 497 | West Hopkins Petroleum Co LP | | Oil & Gas Operator | Dec 2025 |
| 498 | West Side Exploration, LLC | | Oil & Gas Operator | Dec 2025 |
| 499 | Western Reserves Oil Co Inc | Midland, TX 79705 | Oil & Gas Operator | Oct 2020 |
| 500 | Western Reserves Oil Co Inc And Sullivan And Co | | Oil & Gas Operator | Jul 2001 |