| 201 | Cortez Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2016 |
| 202 | Coterra Energy Operating Co. | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 203 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 204 | Couch Donald W | Marlow, OK 73055 | Oil & Gas Operator | Jun 2025 |
| 205 | Countyline Production Co LLC | Duncan, OK 73533 | Oil Operator | Jun 2025 |
| 206 | Cowboy Operating LLC | Oklahoma City, OK 73120 | Oil Operator | Jun 2025 |
| 207 | Cox Edwin L & R Berry | Dallas, TX 75202 | Oil & Gas Operator | Apr 2015 |
| 208 | Cox Exploration, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Nov 1999 |
| 209 | Cox Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2014 |
| 210 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 211 | CRD Investments LLC | Duncan, OK 73533-4226 | Oil Operator | Jun 2025 |
| 212 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 213 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 214 | Cross Timbers Production Co | Oklahoma City, OK 73102-5605 | Oil & Gas Operator | Mar 2005 |
| 215 | Crown Petroleum Company | Duncan, OK 73534-0938 | Oil & Gas Operator | Jan 2011 |
| 216 | Cummings Oil Company | Oklahoma City, OK 73112-6113 | Oil & Gas Operator | Jul 2025 |
| 217 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 218 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 219 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Oct 2025 |
| 220 | Dalcor Energy LLC | Duncan, OK 73534 | Oil & Gas Operator | Jun 2025 |
| 221 | Dale Jimmy | Davis, OK 73030 | Oil & Gas Operator | Mar 2015 |
| 222 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 223 | Darwin Allen Dba Wil-Mar Operations | Duncan, OK 73534-1566 | Oil & Gas Operator | Oct 2016 |
| 224 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Jul 2025 |
| 225 | Davco Productions Inc | Springer, OK 73458-8191 | Oil & Gas Operator | Jun 2021 |
| 226 | Davon Drilling Company | Oklahoma City, OK 73113-0665 | Oil & Gas Operator | Mar 2015 |
| 227 | Dawson Resources Inc | Franktown, CO 80116 | Oil & Gas Operator | Mar 2015 |
| 228 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 229 | Dby Investments LLC | Lago VIsta, TX 78645-8011 | Oil & Gas Operator | Nov 2016 |
| 230 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 231 | Dean'S Well Servicing Inc | Ratliff City, OK 73481 | Oil & Gas Operator | Jun 2025 |
| 232 | Dehart Company (The) | Ardmore, OK 73402 | Oil & Gas Operator | Jul 2025 |
| 233 | Delta Petroleum Inc | Houston, TX 77269-1007 | Oil & Gas Operator | May 2009 |
| 234 | Denveramerican Petro LLC | | Oil & Gas Operator | May 2006 |
| 235 | Dette Oil Corporation | Oklahoma City, OK 73162-6249 | Oil & Gas Operator | Oct 2015 |
| 236 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 237 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 238 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 239 | Diamond Cross Oil Co LLC | Ponca City, OK 74601-1104 | Oil & Gas Operator | Jun 2025 |
| 240 | Dickerson Dennis | Velma, OK 73491 | Oil Operator | Jun 2025 |
| 241 | Dinsmore C E | Enid, OK 73702 | Oil & Gas Operator | May 2009 |
| 242 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Oct 2025 |
| 243 | DM Petroleum LLC | Duncan, OK 73533 | Oil Operator | Jun 2025 |
| 244 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 245 | Dominion Exp Midcontinent Inc | Oklahoma City, OK 73134-2616 | Oil & Gas Operator | Oct 2024 |
| 246 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 247 | Dorchester Resources LP | Oklahoma City, OK 73154-8879 | Oil & Gas Operator | Aug 2021 |
| 248 | Dorey Oil Corporation | Healdton, OK 73438-0856 | Oil Operator | Apr 2014 |
| 249 | Dotson Jack M Operating Co | Norman, OK 73072-6649 | Oil Operator | Oct 1993 |
| 250 | Downhole Oil & Gas Tech LLC | Countyline, OK 73152-0027 | Oil Operator | Oct 2009 |
| 251 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 252 | Dunn Energy LLC | Skiatook, OK 74070-4046 | Oil Operator | Sep 2022 |
| 253 | Dyno Energy LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jun 2025 |
| 254 | Ea Petroleum Inc | Norman, OK 73072-4147 | Oil & Gas Operator | May 2006 |
| 255 | Eagle Minerals & Oil Prop Inc | Tulsa, OK 74119 | Oil & Gas Operator | Jan 2002 |
| 256 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Jun 2025 |
| 257 | Earlsboro Energies Corporation | Oklahoma City, OK 73116-3605 | Oil & Gas Operator | Jun 2025 |
| 258 | Easterwood D E | Duncan, OK 73533-1013 | Oil & Gas Operator | Jun 2001 |
| 259 | Eby Frank V Corporation | Yukon, OK 73085-0860 | Oil Operator | Sep 2016 |
| 260 | Echo Production Inc | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 261 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 262 | Edwards Jr L A | Duncan, OK 73534-1348 | Oil & Gas Operator | Sep 1992 |
| 263 | Edwards Oil & Gas Company | Oklahoma City, OK 73156-0386 | Oil & Gas Operator | Mar 2015 |
| 264 | Eec Inc | Norman, OK 73069-6344 | Oil & Gas Operator | Jun 2025 |
| 265 | Egolf Operating Company | Oklahoma City, OK 73114-7899 | Oil & Gas Operator | Apr 1998 |
| 266 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 267 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Jul 2025 |
| 268 | Emjo Operations Inc | Marlow, OK 73055-8803 | Oil & Gas Operator | Jun 2025 |
| 269 | Emo Inc | Eufaula, OK 74432-0841 | Oil & Gas Operator | Apr 2020 |
| 270 | Empire Operating LLC | Lawton, OK 73501 | Oil Operator | Jun 2025 |
| 271 | Encana Energy Resources Inc | Denver, CO 80202-2828 | Oil & Gas Operator | Feb 2024 |
| 272 | Energy Operating Corporation | Plano, TX 75093-4409 | Oil & Gas Operator | Sep 2013 |
| 273 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 274 | Ennex, Inc. | | Oil & Gas Operator | Oct 1993 |
| 275 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 276 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 277 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 278 | Essman Energy, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2019 |
| 279 | Evergreen Operating Corp | Denver, CO 80202 | Oil & Gas Operator | Dec 2019 |
| 280 | Excel Operating Inc | Dallas, TX 75234-7300 | Oil & Gas Operator | Jun 2022 |
| 281 | Exploration Associates II LLC | Oklahoma City, OK 73102-8815 | Oil & Gas Operator | Jan 2013 |
| 282 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 283 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Jul 2025 |
| 284 | Fahrenheit Petroleum Co Inc | | Oil & Gas Operator | Mar 2015 |
| 285 | Fairway Resources Operating III LLC | Houston, TX 77002-2728 | Oil & Gas Operator | Jun 2025 |
| 286 | Farmers Energy Corporation | Tulsa, OK 74103-3525 | Oil & Gas Operator | Nov 2021 |
| 287 | FBF Energy LLC | Tulsa, OK 74120 | Oil & Gas Operator | Jul 2025 |
| 288 | Femco Services Inc | Lindsay, OK 73052-0632 | Oil & Gas Operator | Nov 2006 |
| 289 | Ferguson Oil Company Inc | | Oil & Gas Operator | Apr 1994 |
| 290 | Fleetwood K Phil Oil Properties | Marlow, OK 73055 | Oil & Gas Operator | Jun 2025 |
| 291 | Fletcher Oil LLC | Ratliff City, OK 73481 | Oil & Gas Operator | Jun 2025 |
| 292 | Foreman Enterprises, Inc. | Edmond, OK 73003 | Oil & Gas Operator | May 2025 |
| 293 | Forest Oil Permian Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 294 | Four-O-One Corporation | Edmond, OK 73013-1977 | Oil & Gas Operator | Mar 2015 |
| 295 | FP Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2008 |
| 296 | Fpco Oil & Gas Co. | New Orleans, LA 70160 | Oil & Gas Operator | Jun 2025 |
| 297 | Freddie McCord Dba Fred McCord | Comanche, OK 73529 | Oil & Gas Operator | Jun 2024 |
| 298 | Freeport-McMoran Inc | New Orleans, LA 70160 | Oil & Gas Operator | Apr 1997 |
| 299 | Fremont Energy Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Dec 2004 |
| 300 | Fremont Exploration, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Nov 2014 |