| 401 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 402 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | May 2024 |
| 403 | V/J Oil Company | Yancey, TX 78886 | Oil & Gas Operator | Oct 2015 |
| 404 | Vac-U-Lift Production Co.,Inc. | Lake Forest, CA 92630 | Oil & Gas Operator | May 2024 |
| 405 | Venus Oil Company | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2002 |
| 406 | Verdun Oil & Gas LLC | Houston, TX 77024 | Oil & Gas Operator | May 2024 |
| 407 | Vermillion Production, Inc. | Pearsall, TX 78061 | Oil & Gas Operator | May 2024 |
| 408 | Virtex Operating Company, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2023 |
| 409 | Virtex Petroleum Company, Inc. | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Jan 2008 |
| 410 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 411 | Wallis Energy, Inc. | Austin, TX 78746 | Oil & Gas Operator | May 2024 |
| 412 | WCS Oil & Gas Corporation | Dallas, TX 75209 | Oil & Gas Operator | Aug 2021 |
| 413 | West Bay Exploration Company | Muenster, TX 76252 | Oil & Gas Operator | Feb 2024 |
| 414 | Western Field Exploration, Inc. | Dilley, TX 78017 | Oil & Gas Operator | May 2024 |
| 415 | White Marlin Operating Company, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2024 |
| 416 | Whittier Operating Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2007 |
| 417 | Wilbanks, Bruce A. | Midland, TX 79701 | Oil & Gas Operator | Aug 1996 |
| 418 | Williamson Operating Co. | Uvalde, TX 78801 | Oil & Gas Operator | May 2024 |
| 419 | Wilmoth Interests, Inc. | Marion Center, PA 15759 | Oil & Gas Operator | Dec 2023 |
| 420 | Wilson, Don H., Inc. | Elkhart, TX 75839 | Oil & Gas Operator | May 2019 |
| 421 | Windsor Exploration Company | Dallas, TX 75204 | Oil & Gas Operator | Jan 1994 |
| 422 | Wineland Oil - LLC | Hays, KS 67601 | Oil Operator | Jan 2024 |
| 423 | Winn Exploration Co., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2024 |
| 424 | Wolverine Exploration Company | Houston, TX 77002 | Oil & Gas Operator | May 2019 |
| 425 | Yarborough, W. B. | Midland, TX 79701 | Oil & Gas Operator | Nov 1995 |