| 201 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 202 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 203 | Cotton Valley Operating Company | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2000 |
| 204 | Cox, John L. | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 205 | Crestridge DRLG. & Prod.Co.,LLC | Midland, TX 79702 | Oil & Gas Operator | Sep 2023 |
| 206 | Cross Timbers Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 207 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 208 | Crosstex Services, L.L.C. | Tuscola, TX 79562 | Oil Operator | Oct 2025 |
| 209 | Crownquest Operating, LLC | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 210 | Crusader Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Sep 2011 |
| 211 | Crusader Energy II LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 212 | CTL Oil & Gas Corporation | Buchanan Dam, TX 78609 | Oil & Gas Operator | Nov 2020 |
| 213 | Cuervo Resources, Inc. | FT Stockton, TX 79735 | Oil & Gas Operator | Oct 1996 |
| 214 | Cuervo, Inc. | FT Stockton, TX 79735 | Oil & Gas Operator | Oct 2025 |
| 215 | Custer & Wright Operating, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 216 | Cwoc | Big Spring, TX 79721 | Oil & Gas Operator | Oct 2025 |
| 217 | D & B Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2003 |
| 218 | Dakota Resources, Inc. (I) | Midland, TX 79707 | Oil & Gas Operator | Oct 2025 |
| 219 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 220 | Davcro Inc. | Lubbock, TX 79401 | Oil & Gas Operator | Dec 2003 |
| 221 | Day Resources, Inc. | Midland, TX 79707 | Oil & Gas Operator | Aug 1994 |
| 222 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 223 | De IV Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 224 | De3 Operating LLC | Irving, TX 75038 | Oil & Gas Operator | Jun 2021 |
| 225 | Dean Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2019 |
| 226 | Desana Development Corporation | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 227 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 228 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 229 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 230 | Devon SFS Operating Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 231 | DHC, Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 1997 |
| 232 | Diamond Energy, Inc. | Sherman, TX 75091 | Oil & Gas Operator | Oct 2025 |
| 233 | Diamondback E&P LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 234 | Dinero Operating Co | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 235 | Discovery Operating Inc | Midland, TX 79705 | Oil & Gas Operator | Oct 2025 |
| 236 | DJ & T Services, LLC | Abilene, TX 79601 | Oil & Gas Operator | Oct 2025 |
| 237 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 238 | Dominion Operating, LLC | Midland, TX 79708 | Oil Operator | Mar 2018 |
| 239 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2013 |
| 240 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Oct 2025 |
| 241 | Draco Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 242 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 243 | Drilmor, Inc. | Midland, TX 79701 | Oil & Gas Operator | Feb 1998 |
| 244 | Duncan Drilling Co. | Big Spring, TX 79721 | Oil & Gas Operator | Oct 2025 |
| 245 | Dune Oil And Gas, Inc. | Odessa, TX 79768 | Oil & Gas Operator | Aug 2006 |
| 246 | Durham, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2016 |
| 247 | Dyad Petroleum Company | Midland, TX 79710 | Oil & Gas Operator | Sep 2021 |
| 248 | E.G.L. Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 249 | Eagle Natural Resources, LLC | Eunice, NM 88231 | Oil Operator | Oct 2025 |
| 250 | Eagle Rock Operating Company,LLC | Houston, TX 77252 | Oil & Gas Operator | Oct 2015 |
| 251 | Earnest Producing Corporation | Midland, TX 79704 | Oil & Gas Operator | Oct 2025 |
| 252 | Eastland Oil Company, The | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 253 | Eclipse Oil & Gas, Inc. | Midland, TX 79703 | Oil & Gas Operator | Oct 2025 |
| 254 | Eclipse Services, Inc. * | La Grange, TX 78945 | Oil & Gas Operator | Jul 2003 |
| 255 | Ecoserv Environmental SVCS, LLC | Abbeville, LA 70510 | Oil Operator | Oct 2025 |
| 256 | El Ran, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Oct 2025 |
| 257 | Eldorado Oil And Gas, Inc. | Dallas, TX 75230 | Oil & Gas Operator | Nov 1995 |
| 258 | Elevation Resources LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 259 | Elk Meadows Resources LLC | Houston, TX 77037 | Oil & Gas Operator | Jan 2021 |
| 260 | Elk River Resources, LLC | The Woodlands, TX 77382 | Oil & Gas Operator | Oct 2023 |
| 261 | Empire Texas Operating LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 262 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 263 | Encore Energy Partners Operating LLC | Houston, TX 77057 | Oil & Gas Operator | Apr 2015 |
| 264 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | May 2025 |
| 265 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 266 | Energen Resources Corporation | Midland, TX 79701 | Oil & Gas Operator | Jan 2021 |
| 267 | Energy Onramp LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 268 | Energy Production Corporation | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 269 | Energy Resources Oil & Gas Corp. | Amarillo, TX 79102 | Oil & Gas Operator | Jun 1994 |
| 270 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 271 | Energyquest II, LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Jun 2025 |
| 272 | Enerquest Oil & Gas LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jun 2025 |
| 273 | Enerstar Resources, L.C. | Midland, TX 79701 | Oil & Gas Operator | Apr 1999 |
| 274 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 275 | Enex Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 276 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 277 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 278 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 279 | Ernmar Investments, Inc. | Edmond, OK 73083 | Oil & Gas Operator | Oct 2025 |
| 280 | Escondido Bay Corporation | Dallas, TX 75202 | Oil Operator | Oct 2025 |
| 281 | Estoril Producing Corporation | Midland, TX 79701 | Oil & Gas Operator | Apr 1994 |
| 282 | Et Gathering & Processing LLC | Dallas, TX 75225 | Oil Operator | Dec 2024 |
| 283 | Etc Texas Pipeline, LTD. | Dallas, TX 75225 | Oil Operator | Sep 2023 |
| 284 | Etl Hydrocarbons, Inc. | Andrews, TX 79714 | Oil & Gas Operator | Oct 2025 |
| 285 | Eureka Prospecting Company | Wimberley, TX 78676 | Oil & Gas Operator | Jun 2023 |
| 286 | Ewt Operating Company | Andrews, TX 79714 | Oil & Gas Operator | Oct 2025 |
| 287 | Exchange Exploration & Production Co. | Dallas, TX 75219 | Oil & Gas Operator | Jun 2025 |
| 288 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jun 2025 |
| 289 | Exl Petroleum, LP | Midland, TX 79705 | Oil & Gas Operator | Jun 2017 |
| 290 | Expro Engineering, Inc. | Fort Worth, TX 76179 | Oil & Gas Operator | Oct 2025 |
| 291 | Extex Operating Company | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 292 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 293 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 294 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Jul 2025 |
| 295 | F & M Oil & Gas Co | Midland, TX 79702 | Oil & Gas Operator | Feb 2000 |
| 296 | Fagadau Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2006 |
| 297 | Famcor Oil, Inc. | Scottsdale, AZ 85260 | Oil & Gas Operator | Sep 2020 |
| 298 | Fasken Oil And Ranch, LTD. | Midland, TX 79707 | Oil & Gas Operator | Oct 2025 |
| 299 | Fasken, Barbara | Midland, TX 79701 | Oil & Gas Operator | Dec 1995 |
| 300 | FDL Operating, LLC | Judson, TX 75660 | Oil & Gas Operator | Oct 2025 |