| 201 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Nov 2025 |
| 202 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2026 |
| 203 | Enex Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 204 | Enexco, Inc. | Dallas, TX 75243 | Oil & Gas Operator | Mar 2017 |
| 205 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 206 | Ensource Inc | Midland, TX 79705 | Oil & Gas Operator | Aug 1998 |
| 207 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 208 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |
| 209 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 210 | EP Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 211 | Esco Exploration, Inc | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 212 | Esenjay Exploration, Inc | Houston, TX 77042 | Oil & Gas Operator | Nov 2025 |
| 213 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 214 | Esperanza Energy Corp. | Prosper, TX 75078 | Oil & Gas Operator | Mar 2015 |
| 215 | Evergreen Operating Corp | Denver, CO 80202 | Oil & Gas Operator | Dec 2019 |
| 216 | Evolution Energy LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Nov 2025 |
| 217 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Nov 2025 |
| 218 | Exploration Associates II LLC | Oklahoma City, OK 73102-8815 | Oil & Gas Operator | Jan 2013 |
| 219 | Express Oil & Gas LLC | Oklahoma City, OK 73142-3017 | Oil & Gas Operator | Dec 2025 |
| 220 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Feb 2026 |
| 221 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Sep 2025 |
| 222 | Fairway Resources Operating III LLC | Houston, TX 77002-2728 | Oil & Gas Operator | Nov 2025 |
| 223 | Faulconer Energy, LLC | Tyler, TX 75711 | Oil & Gas Operator | Feb 2026 |
| 224 | Faulconer, Vernon E., Inc. | Tyler, TX 75711 | Oil & Gas Operator | Dec 2025 |
| 225 | Faulkner Corporation | Oklahoma City, OK 73154-9704 | Oil & Gas Operator | Jan 2017 |
| 226 | FDL Operating, LLC | Judson, TX 75660 | Oil & Gas Operator | Feb 2026 |
| 227 | Femco SWD Inc | Enid, OK 73702-3907 | Oil Operator | Mar 2014 |
| 228 | Ferraro Energy Corporation | Oklahoma City, OK 73114-6629 | Oil & Gas Operator | Aug 2013 |
| 229 | Flag Transport Inc | Shattuck, OK 73858-0848 | Oil Operator | Dec 2014 |
| 230 | Flow Production Company | Midland, TX 79708 | Oil & Gas Operator | Mar 2005 |
| 231 | Focus Energy, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Nov 2019 |
| 232 | Foreman Enterprises Inc | Edmond, OK 73003 | Oil & Gas Operator | Oct 2025 |
| 233 | Forest Oil Permian Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 234 | Four Seas Exploration LLC | Oklahoma City, OK 73101-1557 | Oil & Gas Operator | Dec 2019 |
| 235 | Four Square Oil Company Inc | Kellyville, OK 74039 | Oil Operator | Mar 2011 |
| 236 | FP Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2008 |
| 237 | Franks Oil & Gas Inc | Cookson, OK 74427-0310 | Oil & Gas Operator | Oct 1998 |
| 238 | French & Walker Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 1993 |
| 239 | Frisco Energy, L.L.C. | Tulsa, OK 74105 | Oil & Gas Operator | Nov 2025 |
| 240 | Frontier Operating Corporation | Albany, TX 76430 | Oil & Gas Operator | Feb 2026 |
| 241 | Fuksa Investments Inc | Hennessey, OK 73742 | Oil & Gas Operator | Dec 2025 |
| 242 | FX Energy Operating, LLC | Canadian, TX 79014 | Oil & Gas Operator | Feb 2026 |
| 243 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 244 | Gel Oil & Gas Inc | Wetumka, OK 74883-6238 | Oil & Gas Operator | Jul 2016 |
| 245 | Gene Cook Inc | Woodward, OK 73801 | Oil & Gas Operator | Dec 2025 |
| 246 | General Atlantic Resources Inc | Denver, CO 80202 | Oil & Gas Operator | Jan 2022 |
| 247 | General Exploration Inc | | Oil & Gas Operator | Aug 2001 |
| 248 | Geo American Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2025 |
| 249 | Geodyne Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2015 |
| 250 | Geodyne Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2010 |
| 251 | Gilco Oil Inc | Ada, OK 74820 | Oil & Gas Operator | May 2019 |
| 252 | Golden Gas Energies Inc | | Oil & Gas Operator | Jan 1999 |
| 253 | Golden Gas Production Company | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2025 |
| 254 | Gomaco Operating Company | Tulsa, OK 74115 | Oil & Gas Operator | Dec 2025 |
| 255 | Gothic Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2015 |
| 256 | Gothic Production Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2016 |
| 257 | Grasen Energy, Inc. | Amarillo, TX 79159 | Oil & Gas Operator | Aug 2013 |
| 258 | Great Horned Owls, LLC | Katy, TX 77494 | Oil & Gas Operator | Nov 2025 |
| 259 | Greenhead Energy Operating LLC | Oklahoma City, OK 73131 | Oil & Gas Operator | Dec 2025 |
| 260 | Ground Development Company Inc | Dallas, TX 75229-0377 | Oil & Gas Operator | Jan 2013 |
| 261 | Gulf Exploration, LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jan 2026 |
| 262 | Gulf Production Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Apr 2015 |
| 263 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 264 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 265 | H G & G Inc | Edmond, OK 73034 | Oil & Gas Operator | Jan 2006 |
| 266 | Hadaway Consulting And Engineering LLC | Canadian, TX 79014 | Oil & Gas Operator | Nov 2025 |
| 267 | Hadaway Engineering Inc | Canadian, TX 79014 | Oil & Gas Operator | Jul 2015 |
| 268 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Oct 2025 |
| 269 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 270 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 271 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Nov 2025 |
| 272 | Harding And Shelton Exploration LLC | Oklahoma City, OK 73101-1557 | Oil & Gas Operator | Nov 2025 |
| 273 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 274 | Harrell Petroleum Inc | Oklahoma City, OK 73102-7201 | Oil & Gas Operator | Oct 2017 |
| 275 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 276 | HCL Inc | Woodward, OK 73802-1074 | Oil Operator | Mar 2015 |
| 277 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 278 | Henderson Don Inc | Oklahoma City, OK 73134-1753 | Oil & Gas Operator | Aug 2013 |
| 279 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 280 | Highland Oil & Gas LLC | Houston, TX 77079-7220 | Oil & Gas Operator | Feb 2015 |
| 281 | Highmark Energy Operating LLC | Dallas, TX 75222 | Oil & Gas Operator | Feb 2026 |
| 282 | Highway 15 SWD LLC | Shattuck, OK 73858 | Oil Operator | Oct 2021 |
| 283 | Highway 60 SWD LLC | Shattuck, OK 73858-0848 | Oil Operator | Jul 2019 |
| 284 | Hill John H | Dallas, TX 75240-7077 | Oil & Gas Operator | Jul 2015 |
| 285 | Himco Oil & Gas Inc | Enid, OK 73702 | Oil & Gas Operator | Nov 2025 |
| 286 | Hines Oil & Gas LLC | Elk City, OK 73644-9373 | Gas Operator | Aug 2021 |
| 287 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | Dec 2025 |
| 288 | Hog Operating LLC | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 289 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Feb 2026 |
| 290 | Home-Stake Royalty Corp., The | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2014 |
| 291 | Hondo Oil & Gas Company | Roswell, NM 88202 | Oil & Gas Operator | Aug 2006 |
| 292 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 293 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 294 | Houseco Petroleum Inc | Bristow, OK 74010-0842 | Oil & Gas Operator | Aug 2002 |
| 295 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Feb 2026 |
| 296 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 297 | Hulen Operating Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Feb 2026 |
| 298 | Hunt Energy Corporation | | Oil & Gas Operator | Feb 2002 |
| 299 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Feb 2026 |
| 300 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |