| 201 | Trio Operating Company, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2006 |
| 202 | True Oil LLC | Casper, WY 82602 | Oil & Gas Operator | May 2026 |
| 203 | TXP Operating Co. | | Oil & Gas Operator | Jul 1992 |
| 204 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 205 | Vanguard Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 206 | W. H. Hunt Trust Estate | | Oil & Gas Operator | Mar 1997 |
| 207 | Ward-Williston Company | | Oil & Gas Operator | Apr 2014 |
| 208 | Wesco Operating Inc | Casper, WY 82602 | Oil & Gas Operator | May 2026 |
| 209 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 210 | White Butte Oil Operations, LLC | | Oil & Gas Operator | May 2026 |
| 211 | White Rock Oil & Gas, LLC | Plano, TX 75024 | Oil & Gas Operator | Jul 2026 |
| 212 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Jul 2026 |
| 213 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 214 | Williston Industrial Supply Corporation | Williston, ND 58801 | Oil & Gas Operator | Mar 2012 |
| 215 | WPX Energy Williston, LLC | | Oil & Gas Operator | Sep 2025 |
| 216 | Wyoming Resources Corporation | Rapid City, SD 57702 | Oil & Gas Operator | Oct 2018 |
| 217 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2026 |
| 218 | Zavanna Energy Operating, LLC | | Oil & Gas Operator | May 2026 |
| 219 | Zenergy Inc | Tulsa, OK 74136 | Oil & Gas Operator | May 2026 |
| 220 | Zenergy Operating Company, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Dec 2016 |
| 221 | Zinke & Trumbo, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2007 |