| 601 | Uebelhor, Theodore | | Oil Operator | Dec 2023 |
| 602 | Union Operating Corp | Lakewoord, CO 80215 | Oil Operator | Dec 2023 |
| 603 | Union Petro Inc | Uniontown, KY 42461 | Oil Operator | Dec 2023 |
| 604 | United Fuel Gas Co | | Oil & Gas Operator | Dec 2022 |
| 605 | United Well Completion, Inc | Corbin, KY 40701 | Oil & Gas Operator | Dec 2023 |
| 606 | Universal Operating, Inc | Evansville, IN 47715 | Oil & Gas Operator | Dec 2023 |
| 607 | Unknown | Houston, TX 77208 | Oil & Gas Operator | Dec 2023 |
| 608 | Van Lingen, Peter | Nashville, TN 37215 | Oil Operator | Dec 2023 |
| 609 | Vandiver, Tony E | Island, KY 42350 | Oil Operator | Dec 2023 |
| 610 | Viking Exploration, LLC | Mousie, KY 41839 | Oil & Gas Operator | Dec 2023 |
| 611 | Viking Oil & Gas, LLC | Caneyville, KY 42721 | Oil & Gas Operator | Dec 2023 |
| 612 | Vinland Energy Operations, LLC | Lexington, KY 40509 | Oil & Gas Operator | Dec 2023 |
| 613 | Vogler, John F | Greenville, KY 42345 | Oil Operator | Dec 2023 |
| 614 | W W Pet Service, Inc | Dixon, KY 42409 | Oil & Gas Operator | Dec 2022 |
| 615 | Walker Resources Co, LLC | | Oil & Gas Operator | Dec 2013 |
| 616 | War Creek Energy, LLC | Lawrenceburg, KY 40342 | Oil & Gas Operator | Dec 2018 |
| 617 | Watts, J R | | Oil Operator | Dec 2009 |
| 618 | Weal DRLG Co, Inc | Madisonville, KY 42431 | Oil & Gas Operator | Dec 2023 |
| 619 | Wema Natural Res, Inc | Sharon Grove, KY 42280 | Oil Operator | Dec 2021 |
| 620 | West Bay Exploration Company | Muenster, TX 76252 | Oil & Gas Operator | Dec 2025 |
| 621 | West Gas Inc | | Oil & Gas Operator | Dec 2017 |
| 622 | Wheeler Oil, LTD | Isonville, KY 41149 | Oil & Gas Operator | Dec 2023 |
| 623 | Whitney Oil & Gas Co, LLC | | Oil & Gas Operator | Dec 2017 |
| 624 | Whittington Energy Co. | Melbourne, FL 32901 | Oil & Gas Operator | Feb 2026 |
| 625 | Wigner, David H Jr | Franklin, KY 42134 | Oil Operator | Dec 2023 |
| 626 | Wildcat Energy Corp | | Oil & Gas Operator | Dec 2015 |
| 627 | Wildcat Exploration, LLC | Glasgow, KY 42141 | Oil Operator | Dec 2023 |
| 628 | Wildcat Oil, LLC | Sebree, KY 42455 | Oil Operator | Dec 2021 |
| 629 | Wilhelm, Robert V | Russellville, KY 42276 | Gas Operator | Dec 2023 |
| 630 | William B Renfro LLC | | Oil Operator | Dec 2020 |
| 631 | Williams, Floyd E | | Oil Operator | Dec 2015 |
| 632 | Williams, John E | Scottsville, KY 42164 | Oil Operator | Dec 2015 |
| 633 | Wilson, Bruce Oil Inc | Columbia, KY 42728 | Oil Operator | Dec 2023 |
| 634 | Wilson, Ernest L | Morganfield, KY 42437 | Oil Operator | Dec 2023 |
| 635 | Wiser Oil Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2023 |
| 636 | Wood, Clarence & Lacy, W F | | Oil Operator | Dec 2019 |
| 637 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Feb 2026 |
| 638 | Yates Drilling Company | Artesia, NM 88210 | Oil & Gas Operator | Dec 2021 |
| 639 | Yost, Barbra E | | Oil Operator | Dec 2018 |
| 640 | Young Oil Corporation | | Oil & Gas Operator | Dec 2019 |
| 641 | Zaveri Oil & Gas LTD | Albany, KY 42602 | Oil Operator | Dec 2006 |
| 642 | Zenithal LLC | Isonville, KY 41149 | Oil & Gas Operator | Dec 2023 |