| 601 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 602 | Watkins Production Company | Dallas, TX 75229 | Oil & Gas Operator | Feb 2008 |
| 603 | Weaver Global Operating, LLC | Colleyville, TX 76034 | Oil Operator | Sep 2026 |
| 604 | Wells Oilfield Services, Inc. | Graham, TX 76450 | Oil & Gas Operator | Sep 2026 |
| 605 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 606 | West Inland Energy, Inc. | Fort Worth, TX 76179 | Oil & Gas Operator | Jan 2026 |
| 607 | Western Energy Group, LLC | Leander, TX 78641 | Oil & Gas Operator | Sep 2026 |
| 608 | Western Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2026 |
| 609 | Western Sky Oil & Gas | Abilene, TX 79604 | Oil & Gas Operator | Aug 2003 |
| 610 | Westico Energy Co. | Abilene, TX 79605 | Oil & Gas Operator | Nov 2004 |
| 611 | Weststar Operating Company | Santa Anna, TX 76878 | Oil & Gas Operator | Mar 2015 |
| 612 | Westwood Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | May 2013 |
| 613 | White, Oscar | Tuscola, TX 79562 | Oil & Gas Operator | Sep 2026 |
| 614 | Whitehead Prod. Co., Inc. | Humble, TX 77338 | Oil & Gas Operator | May 2026 |
| 615 | Whiteside, H. W. | Abilene, TX 79604 | Oil & Gas Operator | Nov 1998 |
| 616 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2026 |
| 617 | Whitt Oil & Gas, Inc. | Albany, TX 76430 | Oil & Gas Operator | Sep 2026 |
| 618 | Whitt, W. J. | Albany, TX 76430 | Oil & Gas Operator | Nov 1996 |
| 619 | Wilbanks, Bruce A. | Midland, TX 79701 | Oil & Gas Operator | Aug 1996 |
| 620 | Wilbanks, Bruce A. Company | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 621 | Wilco Properties, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Jan 2004 |
| 622 | Williams Deville Operating, Inc. | Fort Worth, TX 76116 | Oil & Gas Operator | Sep 2026 |
| 623 | Wilson Well Service Inc. | Cross Plains, TX 76443 | Oil & Gas Operator | Sep 2026 |
| 624 | Wilson, Olan Max | Cisco, TX 76437 | Oil & Gas Operator | Sep 2026 |
| 625 | Winco Oil Inc. | Abilene, TX 79608 | Oil & Gas Operator | Sep 2026 |
| 626 | Windham Resources | Abilene, TX 79608 | Oil & Gas Operator | Sep 2026 |
| 627 | Windham Resources, Inc. | Tuscola, TX 79562 | Oil & Gas Operator | Feb 2004 |
| 628 | Window Operating Co., The | Coleman, TX 76834 | Oil & Gas Operator | Sep 2026 |
| 629 | Woodygreen Resources, LLC | Plano, TX 75093 | Oil & Gas Operator | Sep 2026 |
| 630 | Wylie Bros. Prod. & DRGL. Co,Inc | Baird, TX 79504 | Oil & Gas Operator | Sep 2026 |
| 631 | Wylie, Fred, Jr. | Moran, TX 76464 | Oil & Gas Operator | Oct 2022 |
| 632 | Xtreme Operating Company LLC | Flower Mound, TX 75022 | Oil Operator | Sep 2026 |
| 633 | Yeates, F. L. | Breckenridge, TX 76424 | Oil & Gas Operator | Oct 1997 |
| 634 | Yellow Rose Oil & Gas Oper. Inc. | Cisco, TX 76437 | Oil & Gas Operator | Sep 2026 |
| 635 | Yellow Rose Oil & Gas Operating | Cisco, TX 76437 | Oil & Gas Operator | Jan 1996 |
| 636 | Zachry Oil And Gas Properties | Midland, TX 79708 | Oil & Gas Operator | Sep 2026 |
| 637 | Ziegler-Peru, Inc. | Houston, TX 77027 | Oil & Gas Operator | Dec 2019 |
| 638 | Zzron Inc. | Midland, TX 79704 | Oil & Gas Operator | Aug 2003 |