| 1 | Wadi Petroleum Inc | Houston, TX 77014 | Oil & Gas Operator | May 2018 |
| 2 | Waelder Oil & Gas, Inc. | Fort Smith, AR 72903 | Oil & Gas Operator | Jun 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 | Oct 2025 |
| 6 | Walter Exploration Company | Dallas, TX 75206 | Oil & Gas Operator | Oct 2025 |
| 7 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 8 | Waters Eng. & Operating, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Sep 2013 |
| 9 | Weibye, Carolyn S. | Houston, TX 77098 | Oil & Gas Operator | Oct 2025 |
| 10 | Welder Operating, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Mar 2001 |
| 11 | Welder-Heyer Energy, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Feb 2001 |
| 12 | West Petroleum Corp. | San Antonio, TX 78205 | Oil & Gas Operator | Oct 2009 |
| 13 | Western Gulf Oil & Gas Inc. | Dallas, TX 75360 | Oil & Gas Operator | Jul 2000 |
| 14 | Westhall Associates, Inc. | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Aug 1997 |
| 15 | Westland Oil Development Corp. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2008 |
| 16 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 17 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Oct 2025 |
| 18 | White Stride LLC | Piedmont, OK 73078 | Oil & Gas Operator | Oct 2025 |
| 19 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 20 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 21 | Wilcox Operating Corporation | Shreveport, LA 71115 | Oil & Gas Operator | Oct 2025 |
| 22 | Wild Cat Operating Company | Victoria, TX 77903 | Oil & Gas Operator | Mar 2008 |
| 23 | Williams-Cody, Inc. | Houston, TX 77060 | Oil & Gas Operator | May 1994 |
| 24 | Williamson Oil & Gas, Inc. | Shreveport, LA 71166 | Oil & Gas Operator | Dec 2024 |
| 25 | Wilson Hydrocarbon Inc. | Houston, TX 77066 | Oil & Gas Operator | Oct 2025 |
| 26 | Winn Exploration Co., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 27 | Wofford, C. J. | El Campo, TX 77437 | Oil & Gas Operator | Oct 2025 |
| 28 | Wolfson, I. J. | Wichita Falls, TX 76301 | Oil & Gas Operator | Apr 2002 |
| 29 | Wood Hi Co., Inc. | Victoria, TX 77902 | Oil & Gas Operator | Dec 2004 |