| 201 | Dorchester Resources LP | Oklahoma City, OK 73154-8879 | Oil & Gas Operator | Aug 2021 |
| 202 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 203 | Drake Exploration Inc | Tulsa, OK 74105-4250 | Oil & Gas Operator | Feb 2026 |
| 204 | DRG Energy Inc. | Norman, OK 73026-3171 | Oil & Gas Operator | Jan 2026 |
| 205 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2026 |
| 206 | Durango Exploration LLC | Oklahoma City, OK 73120-5309 | Oil & Gas Operator | Feb 2026 |
| 207 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 208 | Eagle Road Oil LLC | Tulsa, OK 74103-3312 | Oil & Gas Operator | Feb 2026 |
| 209 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Jan 2026 |
| 210 | Earlsboro Energies Corporation | Oklahoma City, OK 73116-3605 | Oil & Gas Operator | Jan 2026 |
| 211 | Eberly & Meade | Oklahoma City, OK 73118 | Oil & Gas Operator | Jul 2002 |
| 212 | Echo E & P LLC | Oklahoma City, OK 73102-6439 | Oil & Gas Operator | Jan 2026 |
| 213 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2026 |
| 214 | Edinger Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2007 |
| 215 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 216 | Eec Inc | Norman, OK 73072 | Oil & Gas Operator | Feb 2026 |
| 217 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 218 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | Feb 2026 |
| 219 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Dec 2025 |
| 220 | Emc Exploration Company Inc | Oklahoma City, OK 73103-3775 | Oil & Gas Operator | Jul 2007 |
| 221 | Encana Energy Resources Inc | Denver, CO 80202-2828 | Oil & Gas Operator | Feb 2024 |
| 222 | Encino Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Apr 2026 |
| 223 | Enernet Inc | Oklahoma City, OK 73102-8004 | Oil & Gas Operator | Nov 2014 |
| 224 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 225 | Entex Petroleum Inc | Oklahoma City, OK 73113 | Oil & Gas Operator | Nov 1997 |
| 226 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 227 | EOG Resources Inc | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 228 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 229 | Esco Exploration, Inc | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 230 | Esenjay Exploration, Inc | Houston, TX 77042 | Oil & Gas Operator | Jan 2026 |
| 231 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 232 | Evolution Energy LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Feb 2026 |
| 233 | Excalibur Resources LLC | Houston, TX 77002-5220 | Oil & Gas Operator | Feb 2026 |
| 234 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jan 2026 |
| 235 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Apr 2026 |
| 236 | Farmers Energy Corporation | Tulsa, OK 74103-3525 | Oil & Gas Operator | Nov 2021 |
| 237 | Faulconer Energy, LLC | Tyler, TX 75711 | Oil & Gas Operator | Apr 2026 |
| 238 | Faulconer, Vernon E., Inc. | Tyler, TX 75711 | Oil & Gas Operator | Feb 2026 |
| 239 | Faulkner Corporation | Oklahoma City, OK 73154-9704 | Oil & Gas Operator | Jan 2017 |
| 240 | Felix Energy LLC | Denver, CO 80202-1467 | Oil & Gas Operator | Jan 2026 |
| 241 | Femco SWD Inc | Enid, OK 73702-3907 | Oil Operator | Mar 2014 |
| 242 | Fisher Ellis R | Bristow, OK 74010-8515 | Oil & Gas Operator | Dec 2015 |
| 243 | Flatlander Energy LLC | Blackwell, OK 74631 | Oil & Gas Operator | Feb 2026 |
| 244 | Fleetwood K Phil Oil Properties | Marlow, OK 73055 | Oil & Gas Operator | Jan 2026 |
| 245 | Flow Production Company | Midland, TX 79708 | Oil & Gas Operator | Mar 2005 |
| 246 | Focus Energy, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Nov 2019 |
| 247 | Forcenergy Inc | Miami, FL 33129 | Oil & Gas Operator | Mar 2015 |
| 248 | Foreman Enterprises Inc | Edmond, OK 73003 | Oil & Gas Operator | Oct 2025 |
| 249 | Forte Energy Corpration | Houston, TX 77024-1209 | Oil & Gas Operator | Jan 1995 |
| 250 | Fossil Creek Energy Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Apr 2026 |
| 251 | Four Seas Exploration LLC | Oklahoma City, OK 73101-1557 | Oil & Gas Operator | Dec 2019 |
| 252 | Four-O-One Corporation | Edmond, OK 73013-1977 | Oil & Gas Operator | Mar 2015 |
| 253 | FP Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2008 |
| 254 | Fremont Exploration, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Nov 2014 |
| 255 | Frontier Operating Corporation | Albany, TX 76430 | Oil & Gas Operator | Apr 2026 |
| 256 | Fuksa Investments Inc | Hennessey, OK 73742 | Oil & Gas Operator | Feb 2026 |
| 257 | FW Midcon I, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2026 |
| 258 | G & N Oil & Gas LLC | Asher, OK 74826 | Oil & Gas Operator | Mar 2025 |
| 259 | G A W Oil Company LLC | Enid, OK 73702-3926 | Oil & Gas Operator | Feb 2026 |
| 260 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 261 | Garrison Bros Pipe & Used Equip Inc | Hinton, OK 73047 | Oil & Gas Operator | Aug 2013 |
| 262 | Gary M Lake & Company | Edmond, OK 73012-8208 | Oil & Gas Operator | Aug 2021 |
| 263 | Gastar Exploration LLC | Tulsa, OK 74136-1921 | Oil & Gas Operator | Jan 2026 |
| 264 | General Atlantic Resources Inc | Denver, CO 80202 | Oil & Gas Operator | Jan 2022 |
| 265 | Geodyne Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2015 |
| 266 | Germany Operating Company | Houston, TX 77090 | Oil & Gas Operator | Sep 2011 |
| 267 | Getty Oil Company | Hays, KS 67601 | Oil & Gas Operator | Mar 2015 |
| 268 | Geyer Brothers Equipment Company | Noble, OK 73068-8540 | Oil & Gas Operator | Mar 2011 |
| 269 | Gilliland Oil And Gas Inc | Hennessey, OK 73742 | Oil & Gas Operator | Feb 2026 |
| 270 | Glacier Petroleum Co Okla Inc | Edmond, OK 73013-1977 | Oil & Gas Operator | Feb 2026 |
| 271 | GLB Exploration Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2026 |
| 272 | Golden Gas Energies Inc | | Oil & Gas Operator | Jan 1999 |
| 273 | Golden Gas Production Company | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2026 |
| 274 | Gothic Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2015 |
| 275 | Gothic Production Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2016 |
| 276 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 277 | Greenhead Energy Operating LLC | Oklahoma City, OK 73131 | Oil & Gas Operator | Feb 2026 |
| 278 | Greenlee Oil And Gas LLC | Norman, OK 73072 | Oil & Gas Operator | Dec 2025 |
| 279 | Griffin Resources LLC | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2026 |
| 280 | Grizzly Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Jan 2026 |
| 281 | Gulf Exploration, LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2026 |
| 282 | Gulfstream Petroleum Corp | | Oil & Gas Operator | Feb 2002 |
| 283 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 284 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 285 | H2ok LLC | Marble Falls, TX 78654 | Oil & Gas Operator | Feb 2026 |
| 286 | Hadson Petro USA Inc | | Oil & Gas Operator | Nov 2016 |
| 287 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Jan 2026 |
| 288 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 289 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 290 | Hamil Oil & Gas LLC | Kingfisher, OK 73750-6500 | Oil & Gas Operator | Feb 2026 |
| 291 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Jan 2026 |
| 292 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 293 | Harrell Verlan W | Oklahoma City, OK 73102-7201 | Oil & Gas Operator | Nov 1999 |
| 294 | Hazelwood Louis J | Albuquerque, NM 87111-6870 | Oil & Gas Operator | Feb 2023 |
| 295 | Hazlewood Oil & Gas Co Inc | Oklahoma City, OK 73139-9353 | Oil & Gas Operator | Apr 2022 |
| 296 | HCM | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 297 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 298 | Hellard Elmer J | Sapulpa, OK 74066 | Oil & Gas Operator | Jan 2026 |
| 299 | Hennessey Oil & Gas LLC | Hennessey, OK 73742-0212 | Oil & Gas Operator | Sep 2024 |
| 300 | Henry Gungoll Operating Inc | Enid, OK 73703 | Oil & Gas Operator | Feb 2026 |