| 1 | Warren E & P Inc | Dallas, TX 75240 | Oil & Gas Operator | Sep 2024 |
| 2 | Washington Energy Exploration | | Oil & Gas Operator | Dec 1997 |
| 3 | Weaver Oil Inc | | Oil & Gas Operator | Oct 2011 |
| 4 | Wellstar Corporation | Northglenn, CO 80233 | Oil & Gas Operator | Sep 2024 |
| 5 | Westech Energy Corporation | Denver, CO 80237 | Oil & Gas Operator | Mar 2011 |
| 6 | Western American Resources LLC | Denver, CO 80202 | Oil & Gas Operator | Jun 2024 |
| 7 | Western Gas Resources Inc | Denver, CO 80202-1955 | Oil & Gas Operator | Dec 2007 |
| 8 | Western Interior Energy Inc. | Denver, CO 80202 | Oil & Gas Operator | Jul 2020 |
| 9 | Western Operating Company | Denver, CO 80204 | Oil & Gas Operator | Sep 2024 |
| 10 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 11 | Wexpro Company | Rock Springs, WY 82902-0458 | Oil & Gas Operator | Sep 2024 |
| 12 | Whisler Enterprise Company | Erie, CO 80516 | Oil & Gas Operator | Oct 2024 |
| 13 | White Rock Oil & Gas, LLC | Plano, TX 75024 | Oil & Gas Operator | Dec 2024 |
| 14 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 15 | Wichita River Oil Corporation | Englewood, CO 80111 | Oil & Gas Operator | Apr 2009 |
| 16 | Wildfire Partners Inc | Ardmore, OK 73402 | Oil & Gas Operator | Dec 2009 |
| 17 | Williams Ted H | | Oil & Gas Operator | Dec 2008 |
| 18 | Win Oil Company | Russell, KS 67665 | Oil & Gas Operator | Jul 2021 |
| 19 | Winter Ridge Energy LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2011 |
| 20 | Wold Energy Partners LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2022 |
| 21 | Wood River Oil & Refining Co | | Oil & Gas Operator | Dec 1998 |
| 22 | WPX Energy Rocky Mountain LLC | Tulsa, OK 74101 | Oil & Gas Operator | Sep 2024 |
| 23 | Wulf Oil Co | | Oil & Gas Operator | Dec 1984 |
| 24 | Wyoming Resources Corporation | Rapid City, SD 57702 | Oil & Gas Operator | Oct 2018 |