| 201 | Townsend Company | Abilene, TX 79608 | Oil & Gas Operator | Dec 2021 |
| 202 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Dec 2024 |
| 203 | Trio Consulting & Management,LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2024 |
| 204 | Trio Operating Company, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2006 |
| 205 | Triumph Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2024 |
| 206 | Tucker Resources, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Aug 2003 |
| 207 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | Dec 2024 |
| 208 | Valero Marketing & Supply Co | San Antonio, TX 78269-6000 | Oil & Gas Operator | Sep 2023 |
| 209 | W & T Offshore, L.L.C. | Houston, TX 77046 | Gas Operator | Jan 1999 |
| 210 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 211 | Westico Energy Co. | Abilene, TX 79605 | Oil & Gas Operator | Nov 2004 |
| 212 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 213 | Westwood Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | May 2013 |
| 214 | Wheat, Buck Resources, Inc. | Eastland, TX 76448 | Oil & Gas Operator | Dec 2009 |
| 215 | Wild Horse Energy | Paducah, TX 79248 | Oil & Gas Operator | Dec 2024 |
| 216 | Williams, A. Oil | Wichita Falls, TX 76308 | Oil Operator | Dec 2024 |
| 217 | Woodbine Petroleum, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Aug 2003 |
| 218 | Young, Marshall R., Oil Co. | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2011 |