| 501 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | May 2024 |
| 502 | Willow Bend Oil LLC | Dallas, TX 75206 | Oil & Gas Operator | May 2024 |
| 503 | Willow Creek Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 2009 |
| 504 | Winchester Operating, Inc. | Bryan, TX 77808 | Oil & Gas Operator | Aug 2001 |
| 505 | Wind River Energy, Inc. | Midland, TX 79710 | Oil & Gas Operator | May 2024 |
| 506 | Winn Operating, LLC | Kilgore, TX 75663 | Oil & Gas Operator | May 2024 |
| 507 | Wiseman, B. W., Jr. | Midland, TX 79702 | Oil & Gas Operator | Dec 2002 |
| 508 | Wiser Oil Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2019 |
| 509 | Wood, McShane & Thams | Midland, TX 79702 | Oil & Gas Operator | Oct 1995 |
| 510 | Woodbine Petroleum, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Aug 2003 |
| 511 | World Producers, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Nov 1994 |
| 512 | Wynne Petroleum Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Nov 1997 |
| 513 | Xeric Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Jul 1997 |
| 514 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 515 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | May 2024 |
| 516 | Yates, Harvey E. Company | Roswell, NM 88201 | Oil & Gas Operator | Dec 2002 |
| 517 | Young, Marshall R., Oil Co. | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2011 |
| 518 | Yukon Exploration Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | May 2024 |