| 201 | T. M. Hopkins | | Oil & Gas Operator | Aug 2007 |
| 202 | Talco Midstream Assets, LTD. | | Oil Operator | May 2017 |
| 203 | Tatco, Inc. | | Oil & Gas Operator | May 1991 |
| 204 | TDX Energy, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2024 |
| 205 | Tellurian Operating LLC | | Oil & Gas Operator | Jun 2024 |
| 206 | Texas Eastern Transm. Corp. | | Oil & Gas Operator | Dec 2002 |
| 207 | Tigco Oil & Gas Co., Inc. | | Oil & Gas Operator | Nov 2014 |
| 208 | Tigner Walker | | Oil & Gas Operator | Dec 2021 |
| 209 | Tola Production Company | Dallas, TX 75367 | Oil & Gas Operator | Mar 2025 |
| 210 | Trebole Operating Company | | Oil Operator | Jul 1979 |
| 211 | Triad Resources Inc | Spring, TX 77389 | Oil & Gas Operator | Dec 2020 |
| 212 | Troy E. Boyd | | Oil Operator | Oct 1998 |
| 213 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 214 | United Gas Pipe Line Co. | | Oil Operator | Aug 1993 |
| 215 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 216 | Varco Oil | | Oil & Gas Operator | Apr 1991 |
| 217 | Vine Energy Operating LP | | Gas Operator | Oct 2021 |
| 218 | Vine Oil & Gas LP | | Gas Operator | Apr 2021 |
| 219 | Vista Corporation | | Oil & Gas Operator | Jan 2011 |
| 220 | Walker-Wilson | | Oil & Gas Operator | Jul 1999 |
| 221 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Mar 2025 |
| 222 | Weiser-Brown Operating Company | Magnolia, AR 71754 | Oil & Gas Operator | Mar 2025 |
| 223 | Wesla Oil & Gas Co., Inc. | | Oil & Gas Operator | Jun 2001 |
| 224 | Whitton Company, Inc. | | Oil & Gas Operator | Jul 2020 |
| 225 | Wicker Oil Co | | Oil & Gas Operator | Feb 1992 |
| 226 | Will-Drill Operating, L.L.C. | Shreveport, LA 71105 | Oil & Gas Operator | Mar 2025 |
| 227 | Will-Drill Production Co., Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Mar 2025 |
| 228 | Wilson Well Service | Loco, OK 73442-0114 | Oil & Gas Operator | Mar 2018 |
| 229 | Winbeau Oil & Gas Co. | | Oil & Gas Operator | Oct 2013 |
| 230 | Winchester Production Company | Shreveport, LA 71129 | Oil & Gas Operator | Nov 2008 |