| 201 | Crown Petroleum Company | Duncan, OK 73534-0938 | Oil & Gas Operator | Jan 2011 |
| 202 | Crusader Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Sep 2011 |
| 203 | Crusader Energy Group Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 2015 |
| 204 | Crusader Energy Group LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Mar 2015 |
| 205 | Crusader Energy II LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 206 | Crusader Energy III LLC | Oklahoma City, OK 73142-1856 | Oil & Gas Operator | Feb 2011 |
| 207 | Crystal Energy Inc | Oklahoma City, OK 73116 | Oil & Gas Operator | Feb 2019 |
| 208 | Cuesta Petroleum Inc | Shawnee, OK 74801-6963 | Oil & Gas Operator | Sep 2025 |
| 209 | Culbreath Oil & Gas Co Inc | Tulsa, OK 74135 | Oil & Gas Operator | Oct 2025 |
| 210 | CVR Supply & Trading, LLC | Sugar Land, TX 77479 | Oil & Gas Operator | Apr 2024 |
| 211 | D & B Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2003 |
| 212 | D & D Pipe & Equipment Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Mar 2005 |
| 213 | D & S Operating | Texhoma, OK 73949 | Oil & Gas Operator | May 2001 |
| 214 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 215 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Dec 2025 |
| 216 | Dabb Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Aug 2020 |
| 217 | Dale George | Elmore City, OK 73433 | Oil & Gas Operator | Aug 2022 |
| 218 | Dalen Resources Oil & Gas Co | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 219 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 220 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 221 | Danco Enterprises Inc | Ada, OK 74820 | Oil Operator | Apr 2008 |
| 222 | Darwin Allen Dba Wil-Mar Operations | Duncan, OK 73534-1566 | Oil & Gas Operator | Oct 2016 |
| 223 | Dash Operating LLC | Oklahoma City, OK 73118-5031 | Oil & Gas Operator | Jul 2025 |
| 224 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Oct 2025 |
| 225 | Daube Exploration Company | Ardmore, OK 73402 | Oil & Gas Operator | Nov 2020 |
| 226 | Davis Henry | Tulsa, OK 74135-3567 | Oil & Gas Operator | Dec 1994 |
| 227 | Davis Operating Company | Elysian Field, TX 75642 | Oil & Gas Operator | Dec 2025 |
| 228 | Davis William W | | Oil Operator | Jun 2024 |
| 229 | Davis, William H. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2014 |
| 230 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Dec 2025 |
| 231 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 232 | Dean'S Well Servicing Inc | Ratliff City, OK 73481 | Oil & Gas Operator | Oct 2025 |
| 233 | Dearing, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2021 |
| 234 | Deck Oil Company | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2020 |
| 235 | Dehart Company (The) | Ardmore, OK 73402 | Oil & Gas Operator | Oct 2025 |
| 236 | Deka Exploration Inc | Oklahoma City, OK 73113-0057 | Oil & Gas Operator | Nov 2019 |
| 237 | Delta D Operations | Wilson, OK 73463 | Oil & Gas Operator | Jul 2014 |
| 238 | Delta D Operations Inc | Ardmore, OK 73401-8678 | Oil & Gas Operator | Apr 2014 |
| 239 | Deminex U S Oil Company | | Oil & Gas Operator | Jan 1998 |
| 240 | Derae Oil Company | Seminole, OK 74868-2617 | Oil & Gas Operator | Feb 1997 |
| 241 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 242 | Diane Oil Company | Oklahoma City, OK 73146 | Oil & Gas Operator | Oct 2025 |
| 243 | Dickerson Oil | Ada, OK 74820 | Oil Operator | Jan 2025 |
| 244 | Dinsmore C E | Enid, OK 73702 | Oil & Gas Operator | May 2009 |
| 245 | Dixie Oil Company Inc | Moore, OK 73153 | Oil & Gas Operator | Nov 1994 |
| 246 | Dixie Petroleum Inc | Cashion, OK 73016 | Oil & Gas Operator | May 2001 |
| 247 | DLB Energy Corporation | Oklahoma City, OK 73118-1401 | Oil & Gas Operator | Dec 2014 |
| 248 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 249 | Douglass Dietz & Daley Inc | Oklahoma City, OK 73154-0125 | Oil & Gas Operator | Aug 2023 |
| 250 | Downhole Oil & Gas Tech LLC | Countyline, OK 73152-0027 | Oil Operator | Oct 2009 |
| 251 | Draw Oil & Gas Inc | | Oil & Gas Operator | Jun 1995 |
| 252 | Duncan Oil & Gas Inc | Norman, OK 73072 | Oil & Gas Operator | Sep 2020 |
| 253 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2025 |
| 254 | Dundee Oil & Supply Inc | Tulsa, OK 74101 | Oil & Gas Operator | Apr 2001 |
| 255 | Dunkin Oil And Gas LLC | Wynewood, OK 73098-9196 | Oil Operator | Jul 2025 |
| 256 | Dunn'S Oil And Gas Lease Management LLC | Ardmore, OK 73401 | Oil & Gas Operator | Oct 2025 |
| 257 | DWJS Inc | Oklahoma City, OK 73159 | Oil & Gas Operator | Sep 2024 |
| 258 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 259 | Dyno Energy LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Oct 2025 |
| 260 | Eagle Energy Production LLC | Tulsa, OK 74136-1935 | Oil & Gas Operator | Mar 2020 |
| 261 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Dec 2025 |
| 262 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Sep 2025 |
| 263 | Echo E & P LLC | Oklahoma City, OK 73102-6439 | Oil & Gas Operator | Oct 2025 |
| 264 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 265 | Edwards Jr L A | Duncan, OK 73534-1348 | Oil & Gas Operator | Sep 1992 |
| 266 | Edwards Oil & Gas Company | Oklahoma City, OK 73156-0386 | Oil & Gas Operator | Mar 2015 |
| 267 | Eec Inc | Norman, OK 73069-6344 | Oil & Gas Operator | Oct 2025 |
| 268 | Egolf Operating Company | Oklahoma City, OK 73114-7899 | Oil & Gas Operator | Apr 1998 |
| 269 | Eichenber A H Co | Tulsa, OK 74105 | Oil & Gas Operator | Oct 2002 |
| 270 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 271 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | Oct 2025 |
| 272 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Oct 2025 |
| 273 | Ellithorp Production LLC | Lindsay, OK 73052-5013 | Oil & Gas Operator | Apr 2019 |
| 274 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Oct 2025 |
| 275 | Energy Exchange Corporation | Oklahoma City, OK 73112 | Oil Operator | Sep 2025 |
| 276 | Energy Production Services LLC | Oklahoma City, OK 73162-4736 | Oil & Gas Operator | Apr 2020 |
| 277 | Energyquest II, LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Oct 2025 |
| 278 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 279 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 280 | EOG Resources Inc | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 281 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 282 | EP Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 283 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 284 | Excelco Energy Inc. | Kingwood, TX 77339 | Oil & Gas Operator | Jul 2018 |
| 285 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Sep 2025 |
| 286 | Exoko Operating Company Inc | Tulsa, OK 74170-0246 | Oil & Gas Operator | Jan 2006 |
| 287 | Explo Oil, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Dec 2025 |
| 288 | Exploration Associates II LLC | Oklahoma City, OK 73102-8815 | Oil & Gas Operator | Jan 2013 |
| 289 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Dec 2025 |
| 290 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Aug 2025 |
| 291 | Falcon Engineering Company, Inc. | Big Rapids, MI 493070818 | Oil & Gas Operator | Jul 2001 |
| 292 | Farmers Energy Corporation | Tulsa, OK 74103-3525 | Oil & Gas Operator | Nov 2021 |
| 293 | FBF Energy LLC | Tulsa, OK 74120 | Oil & Gas Operator | Oct 2025 |
| 294 | FDL Operating, LLC | Judson, TX 75660 | Oil & Gas Operator | Dec 2025 |
| 295 | Femco Services Inc | Lindsay, OK 73052-0632 | Oil & Gas Operator | Nov 2006 |
| 296 | Femco SWD Inc | Enid, OK 73702-3907 | Oil Operator | Mar 2014 |
| 297 | Fletcher Oil LLC | Ratliff City, OK 73481 | Oil & Gas Operator | Oct 2025 |
| 298 | Focus Energy, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Nov 2019 |
| 299 | Fortuna Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2014 |
| 300 | Four Star Oil & Gas Company | Houston, TX 77252 | Oil & Gas Operator | Sep 2025 |