| 1 | Wadi Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Oct 2025 |
| 2 | Wadi Petroleum Inc | Houston, TX 77014 | Oil & Gas Operator | May 2018 |
| 3 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 4 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 5 | Wallis Energy, Inc. | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 6 | Walter Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 7 | Warren American Oil Co | Tulsa, OK 74147 | Oil & Gas Operator | Jul 2025 |
| 8 | Waters Eng. & Operating, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Sep 2013 |
| 9 | Welder Exploration & Prod., Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Dec 2022 |
| 10 | Western Gulf Oil & Gas Inc. | Dallas, TX 75360 | Oil & Gas Operator | Jul 2000 |
| 11 | Western Gulf Oil & Gas, LLC | Bishop, TX 78343 | Oil & Gas Operator | Oct 2025 |
| 12 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 13 | White Marlin Operating Company, LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 14 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Oct 2025 |
| 15 | Whitehead Prod. Co., Inc. | Humble, TX 77338 | Oil & Gas Operator | Jun 2025 |
| 16 | Whitfield Energy | Midland, TX 79702 | Oil & Gas Operator | Jan 1999 |
| 17 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 18 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 19 | Whittington Operating Company | Houston, TX 77069 | Oil & Gas Operator | Oct 2025 |
| 20 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Oct 2025 |
| 21 | Wilson Hydrocarbon Inc. | Houston, TX 77066 | Oil & Gas Operator | Oct 2025 |
| 22 | Wind River Resources Inc | Tulsa, OK 74136-6381 | Oil & Gas Operator | Jun 2010 |
| 23 | Winn Exploration Co., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 24 | Wood Energy Corporation | Baytown, TX 77520 | Oil & Gas Operator | Jun 1999 |
| 25 | WRT Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | May 1998 |
| 26 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 27 | Wynne Petroleum Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Nov 1997 |