| 201 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 202 | Cox Resources Corporation | Dallas, TX 75244 | Oil & Gas Operator | Mar 2015 |
| 203 | Cox Robert L | Blackwell, OK 74631 | Oil & Gas Operator | Dec 2024 |
| 204 | Cox, John L. | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 205 | CPRP Services LLC | Oklahoma City, OK 73102-5804 | Oil & Gas Operator | Jan 2025 |
| 206 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2025 |
| 207 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2024 |
| 208 | Crown Energy Company | Oklahoma City, OK 73106 | Oil & Gas Operator | Jan 2025 |
| 209 | Crude Marketing & Trans Inc | Tulsa, OK 74159 | Oil & Gas Operator | Sep 2017 |
| 210 | Crusader Energy Group Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 2015 |
| 211 | Crystal Energy Inc | Oklahoma City, OK 73116 | Oil & Gas Operator | Feb 2019 |
| 212 | D & D Pipe & Equipment Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Mar 2005 |
| 213 | D & J Oil Co | Kermit, TX 79745 | Oil & Gas Operator | Apr 2025 |
| 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 | Apr 2025 |
| 216 | D.J.F. Services, Inc. | Holdenville, OK 74848 | Oil & Gas Operator | Apr 2025 |
| 217 | Dabb Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Aug 2020 |
| 218 | Daco, Inc. | Spearman, TX 79081 | Oil & Gas Operator | Apr 2025 |
| 219 | Dalcor Energy LLC | Duncan, OK 73534 | Oil & Gas Operator | Feb 2025 |
| 220 | Dalen Resources Oil & Gas Co. | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 221 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 222 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 223 | Daniel Resource Dev Inc | Tomball, TX 77375-8919 | Oil & Gas Operator | Oct 2009 |
| 224 | Davco Productions Inc | Springer, OK 73458-8191 | Oil & Gas Operator | Jun 2021 |
| 225 | Davis J L | | Oil & Gas Operator | Aug 2006 |
| 226 | Davis William H | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2014 |
| 227 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Apr 2025 |
| 228 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Jan 2025 |
| 229 | Dead Horse Oil & Gas LLC | Skiatook, OK 74070-9343 | Oil & Gas Operator | Jun 2015 |
| 230 | Deka Exploration Inc | Oklahoma City, OK 73113-0057 | Oil & Gas Operator | Nov 2019 |
| 231 | Dernick Resources, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Jan 2002 |
| 232 | Dette Oil Corporation | Oklahoma City, OK 73162-6249 | Oil & Gas Operator | Oct 2015 |
| 233 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 234 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2025 |
| 235 | Devon Gas Services, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Aug 2023 |
| 236 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 237 | Diamond A Inc. | Tulsa, OK 74137 | Oil & Gas Operator | Jun 2001 |
| 238 | Diamond Energy Operating Company | Tulsa, OK 74137 | Oil & Gas Operator | Mar 2005 |
| 239 | DLB Energy Corporation | Oklahoma City, OK 73118-1401 | Oil & Gas Operator | Dec 2014 |
| 240 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Apr 2025 |
| 241 | DLKB Operating LLC | Eufaula, OK 74432 | Gas Operator | Jan 2025 |
| 242 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Feb 2025 |
| 243 | Dolphin Energy LLC | Lake Worth, FL 33467 | Oil & Gas Operator | Dec 2024 |
| 244 | Dominion Exp Midcontinent Inc | Oklahoma City, OK 73134-2616 | Oil & Gas Operator | Oct 2024 |
| 245 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 246 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 247 | Drummond, F F | | Oil Operator | Jan 2025 |
| 248 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2025 |
| 249 | Duncan Walter | | Oil & Gas Operator | May 2019 |
| 250 | Durango Energy Inc | Chickasha, OK 73023 | Oil Operator | Dec 1999 |
| 251 | Durango Exploration LLC | Oklahoma City, OK 73120-5309 | Oil & Gas Operator | Feb 2025 |
| 252 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 253 | Eagle Energy PTR I LP | Houston, TX 77064 | Oil & Gas Operator | Feb 2015 |
| 254 | Eagle Exploration Production LLC | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 255 | Eagle Gas Marketing Co | Oklahoma City, OK 73114-2202 | Oil & Gas Operator | Nov 2022 |
| 256 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Apr 2025 |
| 257 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Jan 2025 |
| 258 | Earlsboro Energies Corporation | Oklahoma City, OK 73116-3605 | Oil & Gas Operator | Jan 2025 |
| 259 | Echo E & P LLC | Oklahoma City, OK 73102-6439 | Oil & Gas Operator | Jan 2025 |
| 260 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2025 |
| 261 | Eec Inc | Norman, OK 73069-6344 | Oil & Gas Operator | Feb 2025 |
| 262 | El Paso Natural Gas Company | El Paso, TX 79978 | Oil & Gas Operator | Apr 2013 |
| 263 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 264 | Elder & Vaughn Inc | Oklahoma City, OK 73154-0938 | Oil & Gas Operator | Mar 2008 |
| 265 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Feb 2025 |
| 266 | Emjo Operations Inc | Marlow, OK 73055-8803 | Oil & Gas Operator | Feb 2025 |
| 267 | Enable Gas Transmission LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2022 |
| 268 | Enable Oklahoma Intrastate Transmission LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2022 |
| 269 | Encana Energy Resources Inc | Denver, CO 80202-2828 | Oil & Gas Operator | Feb 2024 |
| 270 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Feb 2025 |
| 271 | Energyquest II, LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Jan 2025 |
| 272 | Enernet Inc | Oklahoma City, OK 73102-8004 | Oil & Gas Operator | Nov 2014 |
| 273 | Enerquest Oil & Gas LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jan 2025 |
| 274 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 275 | Enerwest Trading Co LLC | Duncan, OK 73534 | Oil & Gas Operator | Jan 2025 |
| 276 | Enogex Products Corp | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Jun 2022 |
| 277 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 278 | Entex Petroleum, Inc. | Oklahoma City, OK 73113 | Oil & Gas Operator | Nov 1997 |
| 279 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 280 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 281 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 282 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | May 2022 |
| 283 | EP Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 284 | Esco Exploration, Inc | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 285 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 286 | Eubank Operating Company | Cushing, OK 74023 | Oil & Gas Operator | Aug 2024 |
| 287 | Evolution Energy LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Jan 2025 |
| 288 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jan 2025 |
| 289 | Exok, Inc. | Oklahoma City, OK 73116 | Oil & Gas Operator | Jan 2025 |
| 290 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Apr 2025 |
| 291 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Feb 2025 |
| 292 | Fahrenheit Petroleum Co Inc | | Oil & Gas Operator | Mar 2015 |
| 293 | Fairway Resources Operating III LLC | Houston, TX 77002-2728 | Oil & Gas Operator | Jan 2025 |
| 294 | Far West Development, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 2025 |
| 295 | Faulconer Vernon E Inc | Tyler, TX 75711 | Oil & Gas Operator | Feb 2025 |
| 296 | FBF Energy LLC | Tulsa, OK 74120 | Oil & Gas Operator | Feb 2025 |
| 297 | FDL Operating, LLC | Judson, TX 75660 | Oil & Gas Operator | Apr 2025 |
| 298 | Femco Services Inc | Lindsay, OK 73052-0632 | Oil & Gas Operator | Nov 2006 |
| 299 | Femco SWD Inc | Enid, OK 73702-3907 | Oil Operator | Mar 2014 |
| 300 | Ferguson Oil Company Inc | | Oil & Gas Operator | Apr 1994 |