| 1 | Wagner & Brown, LTD. | Midland, TX 79702 | Oil & Gas Operator | Aug 2014 |
| 2 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2025 |
| 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 2025 |
| 6 | Walter Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 7 | Wapiti Operating, LLC | Houston, TX 77043 | Oil & Gas Operator | Dec 2025 |
| 8 | Well-Co Solutions, LLC | Batson, TX 77519 | Oil Operator | Dec 2025 |
| 9 | Westco Oil Company | Ozona, TX 76943 | Oil & Gas Operator | Dec 2025 |
| 10 | Western Energy Group, LLC | Leander, TX 78641 | Oil & Gas Operator | Dec 2025 |
| 11 | Westland Oil Development Corp. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2008 |
| 12 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 13 | WFMMS, Inc. | Batson, TX 77519 | Oil & Gas Operator | Dec 2025 |
| 14 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Dec 2025 |
| 15 | Whitehead Resources, LTD. | Buna, TX 77612 | Oil & Gas Operator | Dec 2025 |
| 16 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 17 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |