| 1 | Wadi Petroleum Inc | Houston, TX 77014 | Oil & Gas Operator | May 2018 |
| 2 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2024 |
| 3 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 4 | Wainoco Oil & Gas Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2005 |
| 5 | Wallis Energy, Inc. | Austin, TX 78746 | Oil & Gas Operator | Dec 2024 |
| 6 | Wandoo Energy, LLC | The Woodlands, TX 77382 | Oil & Gas Operator | Dec 2024 |
| 7 | Warbonnet Exploration Company | Houston, TX 77056 | Oil & Gas Operator | Apr 2016 |
| 8 | Watco Energy, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Apr 1996 |
| 9 | Weber Energy Corporation | Dallas, TX 75219 | Oil & Gas Operator | Feb 2017 |
| 10 | Weeks Exploration Company | Houston, TX 77063 | Oil & Gas Operator | Aug 1995 |
| 11 | Weiser-Brown Operating Company | Magnolia, AR 71754 | Oil & Gas Operator | Dec 2024 |
| 12 | Wellstar Corporation | Northglenn, CO 80233 | Oil & Gas Operator | Oct 2024 |
| 13 | Western Energy Group, LLC | Leander, TX 78641 | Oil & Gas Operator | Dec 2024 |
| 14 | Westhall Associates, Inc. | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Aug 1997 |
| 15 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 16 | White Marlin Operating Company, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 17 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Dec 2024 |
| 18 | Whitehead Prod. Co., Inc. | Humble, TX 77338 | Oil & Gas Operator | Oct 2024 |
| 19 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 20 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jul 2024 |
| 21 | Wilcox Operating Corporation | Shreveport, LA 71115 | Oil & Gas Operator | Dec 2024 |
| 22 | Willstar Energy GP, LLC | Houston, TX 77279 | Oil & Gas Operator | Sep 2013 |
| 23 | Wilson, Charles B., Jr., Inc. | Houston, TX 77027 | Oil & Gas Operator | Apr 2000 |
| 24 | Winn Exploration Co., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 25 | Wiser Oil Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2019 |
| 26 | WJC, Inc. | Post, TX 79356 | Oil & Gas Operator | Dec 2024 |
| 27 | Wofford, C. J. | El Campo, TX 77437 | Oil & Gas Operator | Dec 2024 |
| 28 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |