| 1 | W. H. Hunt Trust Estate | | Oil & Gas Operator | Mar 1997 |
| 2 | Ward-Williston Company | | Oil & Gas Operator | Apr 2014 |
| 3 | Wesco Operating, Inc. | Casper, WY 82602 | Oil & Gas Operator | Oct 2024 |
| 4 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 5 | White Butte Oil Operations, LLC | | Oil & Gas Operator | Oct 2024 |
| 6 | White Rock Oil & Gas, LLC | Plano, TX 75024 | Oil & Gas Operator | Dec 2024 |
| 7 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 8 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jul 2024 |
| 9 | Williston Industrial Supply Corporation | Williston, ND 58801 | Oil & Gas Operator | Mar 2012 |
| 10 | WPX Energy Williston, LLC | | Oil & Gas Operator | Oct 2024 |
| 11 | Wyoming Resources Corporation | Rapid City, SD 57702 | Oil & Gas Operator | Oct 2018 |