| 601 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Jul 2025 |
| 602 | Well Recycling Company | Olney, TX 76374 | Oil Operator | Aug 2005 |
| 603 | Wells Oilfield Services, Inc. | Graham, TX 76450 | Oil & Gas Operator | Jul 2025 |
| 604 | West Co., The | Wichita Falls, TX 76307 | Oil & Gas Operator | Jun 2016 |
| 605 | West Oil Resources, LLC | Liberty Hill, TX 78642 | Oil & Gas Operator | Jul 2025 |
| 606 | Western Chief Oil & Gas Company | Graham, TX 76450 | Oil & Gas Operator | Jul 2009 |
| 607 | Western Petroleum Resources, Inc | Dallas, TX 75219 | Oil & Gas Operator | May 2021 |
| 608 | WG Oil, LLC | Wichita Falls, TX 76308 | Oil Operator | Jul 2025 |
| 609 | WG Operating, Inc. | Tulsa, OK 74153 | Oil & Gas Operator | May 2012 |
| 610 | Whitaker, Jerry | Sunset, TX 76270 | Oil & Gas Operator | May 2022 |
| 611 | White Knight Production LLC | Lafayette, LA 70505 | Oil & Gas Operator | Feb 2024 |
| 612 | Williams Petroleum Company, Inc. | Burkburnett, TX 76354 | Oil & Gas Operator | Jul 2025 |
| 613 | Willo Oil & Gas Exploration, LLC | Boerne, TX 78006 | Oil & Gas Operator | Jul 2020 |
| 614 | Willowbend Investments, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Jul 2025 |
| 615 | Wilson Petroleum Co. | Springfield, MO 65803 | Oil & Gas Operator | Jul 2025 |
| 616 | Wilson-Shab Corp. | Electra, TX 76360 | Oil & Gas Operator | Jul 2025 |
| 617 | Winchester Exploration, Inc. | Arlington, TX 76013 | Oil & Gas Operator | Aug 2003 |
| 618 | Winfrey Oil Co., Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | May 2016 |
| 619 | Wolfson, I. J. | Wichita Falls, TX 76301 | Oil & Gas Operator | Apr 2002 |
| 620 | Woods Oil Co. | Burkburnett, TX 76354 | Oil & Gas Operator | Jul 2025 |
| 621 | Woods, W.A. Oil Co. | Holliday, TX 76366 | Oil & Gas Operator | Dec 1993 |
| 622 | Wortham Operating, LLC | Holliday, TX 76366 | Oil & Gas Operator | Apr 2023 |
| 623 | Wortham, E. H. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2008 |
| 624 | Wortham, J. R. | Wichita Falls, TX 76310 | Oil & Gas Operator | Aug 2023 |
| 625 | Wortham, Michael R. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2008 |
| 626 | Wright Operating, Inc. | Denison, TX 75020 | Oil & Gas Operator | Jul 2025 |
| 627 | Xeric Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Jul 1997 |
| 628 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 629 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 630 | Xophi Energy, LLC | Arlington, TX 76006 | Oil & Gas Operator | Jul 2025 |
| 631 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 632 | Yarberry, E. E. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2015 |
| 633 | Z&G Operating | Wichita Falls, TX 76302 | Oil Operator | Sep 2011 |
| 634 | Zajac Oil Co. | Electra, TX 76360 | Oil & Gas Operator | Jul 2025 |