| 201 | Fortuna Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2014 |
| 202 | FP Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2008 |
| 203 | FX Energy Operating, LLC | Canadian, TX 79014 | Oil & Gas Operator | Oct 2025 |
| 204 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 205 | Garrison Bros Pipe & Used Equip Inc | Hinton, OK 73047 | Oil & Gas Operator | Aug 2013 |
| 206 | Gas Development Corp. | Broken Arrow, OK 74012 | Oil & Gas Operator | Mar 2015 |
| 207 | Geodyne Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2015 |
| 208 | Geodyne Resources Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2010 |
| 209 | GHK Company LLC (The) | Oklahoma City, OK 73118-1120 | Oil & Gas Operator | Apr 2018 |
| 210 | Glacier Petroleum Co Okla Inc | Edmond, OK 73013-1977 | Oil & Gas Operator | Jul 2025 |
| 211 | GLB Exploration, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2025 |
| 212 | Golden Gas Production Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2025 |
| 213 | Gothic Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2015 |
| 214 | Gothic Production Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2016 |
| 215 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 216 | Grizzly Operating LLC | Houston, TX 77057 | Oil & Gas Operator | Jul 2025 |
| 217 | Gulf Exploration, LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Sep 2025 |
| 218 | H2ok LLC | Marble Falls, TX 78654 | Oil & Gas Operator | Jul 2025 |
| 219 | Hadson Petro USA Inc | | Oil & Gas Operator | Nov 2016 |
| 220 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Jun 2025 |
| 221 | Halcyon Natural Gas LLC | Oklahoma City, OK 73116-9111 | Oil & Gas Operator | Jun 2025 |
| 222 | Hall Edward L | Ada, OK 74820-3321 | Oil & Gas Operator | May 2025 |
| 223 | Hall Energy Company LLC | Oklahoma City, OK 73120-5020 | Oil & Gas Operator | Jul 2022 |
| 224 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2025 |
| 225 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 226 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Jun 2025 |
| 227 | Harrell Petroleum Inc | Oklahoma City, OK 73102-7201 | Oil & Gas Operator | Oct 2017 |
| 228 | Harris Oil & Gas Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2016 |
| 229 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 230 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 231 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Jun 2025 |
| 232 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 233 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | Jul 2025 |
| 234 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Oct 2025 |
| 235 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 236 | HPC Incorporated | Denver, CO 80202 | Oil & Gas Operator | Nov 1998 |
| 237 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 238 | Icon Energy Company | Oklahoma City, OK 73156-1613 | Oil & Gas Operator | Jun 2025 |
| 239 | Impact Energy Operating LLC | Oklahoma City, OK 73172 | Oil & Gas Operator | Aug 2025 |
| 240 | Indian Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | Oct 2025 |
| 241 | Indrex Inc | Tulsa, OK 74133 | Oil & Gas Operator | Dec 2000 |
| 242 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 243 | Intergrated Drill & Expl Inc | Tulsa, OK 74136-1071 | Oil & Gas Operator | Sep 1994 |
| 244 | Internorth Inc | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2014 |
| 245 | J B Drilling Company Inc | Muldrow, OK 74948-6601 | Oil & Gas Operator | Jun 2025 |
| 246 | JCR, Jr - Operating, Inc. | Amarillo, TX 79114 | Oil & Gas Operator | Apr 2022 |
| 247 | Jenex Operating Company | The Woodlands, TX 77380-164280209 | Oil & Gas Operator | May 2019 |
| 248 | JKB Resources LLC | Stigler, OK 74462 | Oil & Gas Operator | Jun 2025 |
| 249 | Jma Energy Company, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jul 2025 |
| 250 | Jma Resources, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Jun 2025 |
| 251 | Jojon Petroleum Company | Dallas, TX 75219 | Oil & Gas Operator | May 2025 |
| 252 | Jones Babe Inc | Floydada, TX 79235-0180 | Oil & Gas Operator | May 2019 |
| 253 | Jubilee Exploration LLC | Ardmore, OK 73401-7526 | Oil & Gas Operator | Dec 2024 |
| 254 | Judge Ken & Lester | Perkins, OK 74059 | Oil & Gas Operator | Aug 2014 |
| 255 | K D S Resources Co | Thomas, OK 73669 | Oil & Gas Operator | May 2025 |
| 256 | K-Tel Petroleum | Englewood, CO 80111-4628 | Oil & Gas Operator | Sep 2007 |
| 257 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Oct 2025 |
| 258 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Jun 2025 |
| 259 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 260 | Kepco Operating, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Jun 2025 |
| 261 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 262 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | May 2025 |
| 263 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 264 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 265 | Key Operating Co., Inc. | Duncan, OK 73534-1284 | Oil & Gas Operator | Jan 2025 |
| 266 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jun 2025 |
| 267 | Kingfisher Resources Inc | Clinton, OK 73601 | Oil & Gas Operator | Jul 2025 |
| 268 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 269 | Klo LLC | Tulsa, OK 74120-2428 | Oil & Gas Operator | Jul 2025 |
| 270 | KNG Producers | Dumas, TX 79029 | Oil & Gas Operator | Oct 2009 |
| 271 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 272 | Kodiak Oil & Gas Inc | Muenster, TX 76252 | Oil & Gas Operator | Oct 2025 |
| 273 | KTP Energy, Inc. | Denver, CO 80226 | Oil & Gas Operator | Aug 2019 |
| 274 | Ladd Petroleum Corp. | Denver, CO 80202 | Oil & Gas Operator | Oct 2004 |
| 275 | Lamamco Drilling Company | Skiatook, OK 74070 | Oil & Gas Operator | Jun 2025 |
| 276 | Lariat Petroleum Inc | Tulsa, OK 74119 | Oil & Gas Operator | Sep 2024 |
| 277 | Larkspur Operating LLC | Oklahoma City, OK 73106 | Oil & Gas Operator | Jul 2025 |
| 278 | Latigo Petroleum, LLC | Pampa, TX 79066 | Oil & Gas Operator | Oct 2025 |
| 279 | LCB Resources LLC | Kingfisher, OK 73750-2322 | Oil & Gas Operator | Jul 2025 |
| 280 | Lear Petroleum Corp | Houston, TX 77210 | Oil & Gas Operator | Mar 2015 |
| 281 | Lear Petroleum Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Aug 1999 |
| 282 | Leede Oil & Gas Inc. | Greenwood VLG, CO 80111 | Oil & Gas Operator | Aug 2003 |
| 283 | Lime Rock Resources A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Jun 2025 |
| 284 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Jun 2025 |
| 285 | Lobar Oil Co LLC | Edmond, OK 73013 | Oil & Gas Operator | Jun 2025 |
| 286 | Locators Oil And Gas Inc | Guthrie, OK 73044 | Oil & Gas Operator | Oct 2022 |
| 287 | Lodestone Operating, Inc. | Portland, TX 78374 | Oil & Gas Operator | Oct 2025 |
| 288 | Longview Production Company | Dallas, TX 75243-3795 | Oil & Gas Operator | May 2025 |
| 289 | Lorentz Oil & Gas LLC | Edmond, OK 73034-7266 | Oil & Gas Operator | Jun 2025 |
| 290 | Louisiana Land & Exploration Co. | Houston, TX 77210 | Oil & Gas Operator | Sep 2013 |
| 291 | LX4, LLC | Laverne, OK 73848 | Oil Operator | Jul 2025 |
| 292 | M E Klein & Associates LLC | Washington, OK 73093-4663 | Oil & Gas Operator | Jul 2025 |
| 293 | M M Energy, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Jul 2025 |
| 294 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 295 | Manuel Corporation | Wichita, KS 67206 | Oil & Gas Operator | Jul 2025 |
| 296 | Marathon Oil Company LLC | Houston, TX 77079 | Oil & Gas Operator | Jul 2025 |
| 297 | Marion Corporation | | Oil & Gas Operator | Jan 2001 |
| 298 | Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Jun 2025 |
| 299 | Marsh Operating Company | Dallas, TX 75221 | Oil & Gas Operator | Jun 2025 |
| 300 | Marshall Oil Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Apr 2017 |