| 501 | Stepco Incorpora | | Oil Operator | Nov 1994 |
| 502 | Stepco Oil, Inc. | Ellinwood, KS 67526 | Oil Operator | Jan 2020 |
| 503 | Stepco, Inc. | Ellinwood, KS 67526 | Oil Operator | Feb 2005 |
| 504 | Stephenson L G & | | Oil Operator | Apr 1987 |
| 505 | Sterling Oil Co. | Sterling, KS 67579 | Oil Operator | Feb 2000 |
| 506 | Sterling Petrole | | Oil & Gas Operator | Sep 1992 |
| 507 | Stoskopf, Wayne | Hoisington, KS 67544 | Oil Operator | Apr 1995 |
| 508 | Stratakan Exploration, LLC | Plainville, KS 67663 | Oil & Gas Operator | Feb 2026 |
| 509 | Supernova Energy, Inc. | Wichita, KS 67226 | Oil & Gas Operator | Nov 2019 |
| 510 | T & C MFG. & Operating, Inc. | Great Bend, KS 67530 | Oil Operator | May 2022 |
| 511 | T-N-T Engineering, Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Jun 2026 |
| 512 | Talon Group LLC | Hays, KS 67601 | Oil Operator | Feb 2026 |
| 513 | Taos Resources Operating Co LLC | Houston, TX 77037 | Oil & Gas Operator | Dec 2019 |
| 514 | Te-Pe Oil & Gas | | Oil & Gas Operator | Feb 2026 |
| 515 | Tengasco, Inc. | Houston, TX 77063 | Oil & Gas Operator | Jan 2026 |
| 516 | Tenison Oil Comp | | Oil Operator | Jan 1993 |
| 517 | Tenneco Oil Comp | | Oil & Gas Operator | Aug 1995 |
| 518 | Texaco Explorati | | Oil & Gas Operator | Dec 1996 |
| 519 | Texaco USA - Mor | | Oil Operator | Aug 1988 |
| 520 | Texas Energies I | | Oil & Gas Operator | Aug 1994 |
| 521 | Texas Energies Inc | Pratt, KS 67124 | Oil & Gas Operator | Aug 1998 |
| 522 | TGT Petroleum Co | | Oil & Gas Operator | Apr 1995 |
| 523 | The Pyramid Corporation, Inc. | Wichita, KS 67206 | Oil & Gas Operator | Dec 2009 |
| 524 | Thomas Garner, Inc. | St John, KS 67576 | Oil & Gas Operator | Feb 2026 |
| 525 | Thunderbird Dril | | Oil & Gas Operator | Nov 1995 |
| 526 | TNT Well Servicing, Inc. | Pratt, KS 67124 | Oil Operator | Jun 2006 |
| 527 | Tomkat Limited | | Oil & Gas Operator | Jul 1995 |
| 528 | Tomkat, LTD. | Wichita, KS 67278 | Oil & Gas Operator | Oct 2009 |
| 529 | Tomlinson Operating, LLC | Ketchum, ID 83340 | Oil & Gas Operator | Oct 2014 |
| 530 | Tomlinson, Sid | Hays, KS 67601 | Oil & Gas Operator | Sep 2002 |
| 531 | Trans Pacific Oil Corporation | Wichita, KS 67202 | Oil & Gas Operator | Mar 2026 |
| 532 | Trek Aec, LLC | Wichita, KS 67202 | Oil & Gas Operator | Feb 2026 |
| 533 | Triton Oil & Gas Corp. | Houston, TX 77002 | Oil & Gas Operator | Nov 2014 |
| 534 | Turnco Drilling, Inc. | Portland, OR 97208 | Oil & Gas Operator | Dec 2009 |
| 535 | Tyluka Operations, LLC | Hays, KS 67601 | Oil Operator | Feb 2026 |
| 536 | Unknown | Houston, TX 77208 | Oil & Gas Operator | Dec 2024 |
| 537 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jun 2026 |
| 538 | Val Energy, Inc. | Wichita, KS 67202 | Oil & Gas Operator | Feb 2026 |
| 539 | Vamco Operations | | Oil & Gas Operator | Feb 2026 |
| 540 | Vess Oil Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2026 |
| 541 | Vicorp Energy In | | Oil Operator | Apr 1988 |
| 542 | Viking Resources | | Oil & Gas Operator | Sep 1995 |
| 543 | Viking Resources, Inc. | Stafford, TX 77477 | Oil & Gas Operator | Jun 2026 |
| 544 | Vincent Oil Corp | Wichita, KS 67202 | Oil & Gas Operator | Feb 2026 |
| 545 | Voigt O & G Comp | | Oil & Gas Operator | Nov 1993 |
| 546 | Vonfeldt Oil Ope | | Oil Operator | Oct 1994 |
| 547 | Vonfeldt, Steven R | Russell, KS 67665 | Oil Operator | Feb 2026 |
| 548 | War Cry, LLC | Russell, KS 67665 | Oil Operator | Feb 2026 |
| 549 | Ward Feed Yard, Inc. | Larned, KS 67550 | Oil & Gas Operator | Mar 2016 |
| 550 | Webco Oil Compan | | Oil Operator | Sep 1989 |
| 551 | Webco Oil Company, Inc. | Hoisington, KS 67544 | Oil Operator | Feb 2026 |
| 552 | Weber Four Oil Co., Inc. | Hoisington, KS 67544 | Oil Operator | Dec 2025 |
| 553 | Weigel, V. Francis - Family Partnership | Gorham, KS 67640 | Oil Operator | Jul 2004 |
| 554 | Well Tech Oil And Gas, Inc. | Wichita, KS 67206 | Oil Operator | Sep 2020 |
| 555 | Westech Energy C | | Oil & Gas Operator | Dec 1996 |
| 556 | Western Oil Comp | | Oil Operator | Aug 1989 |
| 557 | White & Ellis DR | | Oil & Gas Operator | Aug 1995 |
| 558 | White & Ellis Drilling, Inc. | Wichita, KS 67206 | Oil & Gas Operator | Feb 2026 |
| 559 | White Eagle Reso | | Oil Operator | Dec 1996 |
| 560 | White Eagle Resources Corp. | Taos, NM 87571 | Oil & Gas Operator | Jun 2016 |
| 561 | Wilton Petroleum, Inc. | Canton, KS 67428 | Oil & Gas Operator | Feb 2026 |
| 562 | Winona Oil & Gas | | Oil & Gas Operator | Sep 1996 |
| 563 | Wirtz Oil, LLC | Ellinwood, KS 67526 | Oil & Gas Operator | Feb 2026 |
| 564 | Woodman & Iannit | | Oil & Gas Operator | Sep 1996 |
| 565 | Woodman & Iannitti Oil Company | Great Bend, KS 67530 | Oil & Gas Operator | Jan 2003 |
| 566 | Worldwide Energy | | Oil & Gas Operator | May 1989 |
| 567 | Wren Investments | | Oil Operator | Feb 1991 |
| 568 | Yale Oil Association, Inc. | Oklahoma City, OK 73105 | Oil & Gas Operator | Mar 2026 |
| 569 | Yost Oil Operations, Inc. | Russell, KS 67665 | Oil Operator | May 1999 |
| 570 | Yost, M. A. | Russell, KS 67665 | Oil Operator | Aug 1990 |
| 571 | Younger Bernard | | Oil Operator | Nov 1992 |
| 572 | Younger Energy C | | Oil & Gas Operator | Dec 1996 |
| 573 | Younger Energy Company | Wichita, KS 67206 | Oil & Gas Operator | Jun 2026 |
| 574 | Zenith Drilling Corporation | Wichita, KS 67206 | Oil & Gas Operator | Feb 2026 |
| 575 | Zinszer Oil Co., Inc. | Hays, KS 67601 | Oil Operator | Dec 2019 |
| 576 | Zu, LLC | Hays, KS 67601 | Oil Operator | Nov 2025 |