| 601 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 602 | Union Texas Petroleum Corp. | Houston, TX 77252-2120 | Oil & Gas Operator | Dec 2014 |
| 603 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Dec 2024 |
| 604 | United Oil Corporation | Denver, CO 80202-3813 | Oil & Gas Operator | Sep 2024 |
| 605 | Uplands Resources Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Sep 2024 |
| 606 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Dec 2024 |
| 607 | Valar Petroleum Inc | Houston, TX 77069 | Oil & Gas Operator | May 2006 |
| 608 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Dec 2024 |
| 609 | Valero Marketing & Supply Co | San Antonio, TX 78269-6000 | Oil & Gas Operator | Sep 2023 |
| 610 | Valjohn Energy Corporation | Oklahoma City, OK 73142-6090 | Oil & Gas Operator | Sep 2024 |
| 611 | Veenker Resources, Inc. | Oklahoma City, OK 73113 | Oil & Gas Operator | Oct 2024 |
| 612 | Vintage Gas Inc | Tulsa, OK 74119-1029 | Oil & Gas Operator | Jun 2007 |
| 613 | Vintage Marketing Inc | Tulsa, OK 74172 | Oil & Gas Operator | Apr 2003 |
| 614 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Sep 2024 |
| 615 | Vitruvian II Woodford LLC | The Woodlands, TX 77381-5259 | Oil & Gas Operator | May 2019 |
| 616 | VRC Oil & Gas Operating Co | Oklahoma City, OK 73116-1431 | Oil & Gas Operator | Jun 2019 |
| 617 | Waggoner Oil & Gas Corp | Enid, OK 73703-1152 | Oil & Gas Operator | Oct 2024 |
| 618 | Wallace Oil & Gas Inc | Oklahoma City, OK 73156 | Oil & Gas Operator | Dec 2024 |
| 619 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 620 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Sep 2024 |
| 621 | Washita Production Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2006 |
| 622 | Waterford Energy Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 1998 |
| 623 | Weatherly Oil & Gas, LLC | Dallas, TX 75206 | Oil & Gas Operator | Dec 2024 |
| 624 | Weiser-Brown Operating Company | Magnolia, AR 71754 | Oil & Gas Operator | Dec 2024 |
| 625 | Western Gas Resources Inc | Denver, CO 80202-1955 | Oil & Gas Operator | Dec 2007 |
| 626 | Western Oil And Gas Development Corp | Oklahoma City, OK 73103-3735 | Oil & Gas Operator | Oct 2024 |
| 627 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Oct 2024 |
| 628 | WFD Oil Corporation | Edmond, OK 73012-0619 | Oil & Gas Operator | Oct 2024 |
| 629 | Whitaker Energy Inc | Humble, TX 77346-1798 | Oil & Gas Operator | Jul 2024 |
| 630 | White Goat Resources LLC | Yukon, OK 73099 | Oil & Gas Operator | Oct 2024 |
| 631 | White Stone LLC | Waynoka, OK 73860-4801 | Oil & Gas Operator | Jul 2024 |
| 632 | Whitehorse Inc | Saint Charles, MO 63303-4204 | Oil & Gas Operator | Sep 2015 |
| 633 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 634 | Whitmar Exploration Company | Denver, CO 80202 | Oil & Gas Operator | Sep 2024 |
| 635 | Whitmar Operating Company | Tulsa, OK 74103-3515 | Oil & Gas Operator | Apr 2009 |
| 636 | Wil-MC Oil Corporation The | Irving, TX 75015-2510 | Oil & Gas Operator | Mar 1999 |
| 637 | Wildhorse Operating Company | Ardmore, OK 73402 | Oil & Gas Operator | Dec 2024 |
| 638 | Will Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Sep 2024 |
| 639 | Williford Energy Company | Tulsa, OK 74135 | Oil & Gas Operator | Dec 2024 |
| 640 | Williford Resources LLC | Tulsa, OK 74136-1020 | Oil & Gas Operator | Sep 2024 |
| 641 | WM Energy LLC | Asher, OK 74826 | Oil & Gas Operator | Sep 2024 |
| 642 | Woods Petroleum Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 643 | Wynn-Crosby Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Sep 2024 |
| 644 | Xanadu Exploration Company | Broken Arrow, OK 74014 | Oil & Gas Operator | Oct 2024 |
| 645 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 646 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Dec 2024 |
| 647 | Yale Oil Association, Inc. | Oklahoma City, OK 73105 | Oil & Gas Operator | Oct 2024 |
| 648 | Zeal Production Company | Sperry, OK 74073-4714 | Oil & Gas Operator | Sep 2024 |
| 649 | Zimet Brothers Inc | | Oil Operator | Mar 2008 |