| 1 | Wesco Operating, Inc. | Casper, WY 82602 | Oil & Gas Operator | Aug 2025 |
| 2 | Westech Energy Corporation | Denver, CO 80237 | Oil & Gas Operator | Mar 2011 |
| 3 | Western Gas Resources Inc | Denver, CO 80202 | Oil & Gas Operator | Dec 2004 |
| 4 | Western Gas Resources-Sand Wash Inc | | Oil & Gas Operator | Feb 2008 |
| 5 | Western Interior Energy Inc. | Denver, CO 80202 | Oil & Gas Operator | Jul 2020 |
| 6 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 7 | Wexpro Company | Rock Springs, WY 82902-0458 | Oil & Gas Operator | Jul 2025 |
| 8 | Wexpro Development Company | Salt Lake City, UT 84111 | Oil & Gas Operator | Jul 2025 |
| 9 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 10 | Winter Ridge Energy LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2011 |
| 11 | Wold Oil Properties Inc | Denver, CO 80203 | Oil & Gas Operator | Feb 2018 |
| 12 | Wolverine Resources LLC | | Oil & Gas Operator | Jan 2024 |
| 13 | Wyman* Louis M Dba Wyman Inc | | Oil & Gas Operator | Aug 2025 |