| 301 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2025 |
| 302 | Wallis Energy, Inc. | Austin, TX 78746 | Oil & Gas Operator | Jul 2025 |
| 303 | Weatherston, George D. | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2001 |
| 304 | Welder Exploration & Prod., Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Dec 2022 |
| 305 | Welder Operating, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Mar 2001 |
| 306 | Welder-Heyer Energy, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Feb 2001 |
| 307 | Welderxp LTD. | San Antonio, TX 78212 | Oil & Gas Operator | Jul 2025 |
| 308 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 309 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Jul 2025 |
| 310 | Whittier Operating Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2007 |
| 311 | Will-Drill Production Co., Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Jul 2025 |
| 312 | Wineland Oil - LLC | Hays, KS 67601 | Oil Operator | Mar 2025 |
| 313 | Winn Exploration Co., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jul 2025 |
| 314 | Womack Operating, LLC. | Houston, TX 77057 | Oil & Gas Operator | Jul 2025 |
| 315 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 316 | Wynn-Crosby Operating, LTD. | Dallas, TX 75201 | Oil & Gas Operator | Jul 2025 |
| 317 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |