| 301 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 302 | Houseco Petroleum Inc | Bristow, OK 74010-0842 | Oil & Gas Operator | Aug 2002 |
| 303 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Dec 2024 |
| 304 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 305 | Hulen Operating Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Dec 2024 |
| 306 | Hunt Energy Corporation | | Oil & Gas Operator | Feb 2002 |
| 307 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Dec 2024 |
| 308 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 309 | Icon Energy Company | Oklahoma City, OK 73156-1613 | Oil & Gas Operator | Sep 2024 |
| 310 | Inca Oil Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2009 |
| 311 | Indian Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | Dec 2024 |
| 312 | Infinity Hydrocarbons LLC | Houston, TX 77079 | Oil & Gas Operator | Aug 2022 |
| 313 | Internorth Inc | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2014 |
| 314 | Investment Equipment LLC | FT Morgan, CO 80701 | Oil & Gas Operator | Sep 2024 |
| 315 | Ip Petroleum Company, Inc. | Houston, TX 77210 | Oil & Gas Operator | Mar 2008 |
| 316 | Irex Corporation | Englewood, CO 80111 | Oil & Gas Operator | May 2000 |
| 317 | Iron Sights Operating Inc | Stillwater, OK 74076 | Oil & Gas Operator | Jul 2022 |
| 318 | J & R Transports Inc | Woodward, OK 73802 | Oil & Gas Operator | Dec 2006 |
| 319 | J&R Operating | Holliday, TX 76366 | Oil & Gas Operator | Feb 2024 |
| 320 | J-Brex Company | Amarillo, TX 79101 | Oil & Gas Operator | Dec 2024 |
| 321 | JCS Operating LLC | Guymon, OK 73942 | Oil & Gas Operator | Sep 2024 |
| 322 | Jec Operating LLC | Oklahoma City, OK 73114-2717 | Oil & Gas Operator | Sep 2024 |
| 323 | Jico Exploration Inc | Oklahoma City, OK 73118 | Oil & Gas Operator | Nov 2004 |
| 324 | JKB Resources LLC | Stigler, OK 74462 | Oil & Gas Operator | Sep 2024 |
| 325 | Jma Energy Company LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Oct 2024 |
| 326 | Jma Resources, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 2024 |
| 327 | Jo-Allyn Oil Co Inc | Laverne, OK 73848 | Oil & Gas Operator | Oct 2024 |
| 328 | Jones & Pellow Oil Co | Oklahoma City, OK 73118-1115 | Oil & Gas Operator | Feb 2015 |
| 329 | Jones Energy LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Sep 2024 |
| 330 | Jordan Oil & Gas Company | Healdsburg, CA 95448-1919 | Oil & Gas Operator | Mar 1995 |
| 331 | K M Gas Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Dec 2014 |
| 332 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Dec 2024 |
| 333 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Sep 2024 |
| 334 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 335 | KCS Resources, LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 336 | Kechi Energy LLC | Chickasha, OK 73018 | Oil & Gas Operator | Sep 2024 |
| 337 | Keith F. Walker Oil & Gas Co., LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Oct 2024 |
| 338 | Kelly Jr Walter A Opr Co | Stillwater, OK 74076 | Oil & Gas Operator | Apr 2014 |
| 339 | Ken Snyder Inc | Newalla, OK 74857-7107 | Oil & Gas Operator | Sep 2024 |
| 340 | Kennedy & Mitchell, Inc. | Houston, TX 77084 | Oil & Gas Operator | Aug 2013 |
| 341 | Kenneth W. Cory, LTD. | Bellaire, TX 77401 | Oil & Gas Operator | Sep 2024 |
| 342 | Kepco Operating, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2024 |
| 343 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 344 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Jun 2024 |
| 345 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 346 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Dec 2024 |
| 347 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Oct 2024 |
| 348 | Kibtec Oil & Gas Inc | Cashion, OK 73016 | Oil & Gas Operator | Aug 2024 |
| 349 | King Operating Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Dec 2024 |
| 350 | Kingery Drilling Co., Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Oct 2024 |
| 351 | Kingfisher Resources Inc | Clinton, OK 73601 | Oil & Gas Operator | Oct 2024 |
| 352 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Dec 2024 |
| 353 | KNG Producers | Dumas, TX 79029 | Oil & Gas Operator | Oct 2009 |
| 354 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 355 | Krumme Oil Company LLP | Bristow, OK 74010 | Oil & Gas Operator | Oct 2024 |
| 356 | L & L Smith Energy Corporation | Muskogee, OK 74403-8479 | Oil & Gas Operator | Jan 2023 |
| 357 | Lariat Petroleum Inc | Tulsa, OK 74119 | Oil & Gas Operator | Sep 2024 |
| 358 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | Dec 2024 |
| 359 | Larkspur Operating LLC | Oklahoma City, OK 73034 | Oil & Gas Operator | Oct 2024 |
| 360 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 361 | Latigo Oil And Gas Inc | Woodward, OK 73801 | Oil & Gas Operator | Oct 2024 |
| 362 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 363 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Sep 2024 |
| 364 | Lincoln Rock Corporation | Northfield, IL 60093 | Oil & Gas Operator | Jul 2003 |
| 365 | Lobo Exploration Company | Yukon, OK 73099 | Oil & Gas Operator | Sep 2024 |
| 366 | Lowry Exploration Inc | Tulsa, OK 74119 | Oil & Gas Operator | Oct 2024 |
| 367 | LX4 LLC | Gage, OK 73843 | Oil Operator | Jul 2024 |
| 368 | M B Oilfield Services | Oklahoma City, OK 73136 | Oil & Gas Operator | Jun 2003 |
| 369 | M V Purchasing LLC | Wichita, KS 67202 | Oil & Gas Operator | Sep 2024 |
| 370 | Mackellar Inc | Oklahoma City, OK 73116-7101 | Oil & Gas Operator | Oct 2024 |
| 371 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 372 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Oct 2024 |
| 373 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | Sep 2024 |
| 374 | Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Oct 2024 |
| 375 | Martin'S Resources LLC | Woodward, OK 73801-5641 | Oil & Gas Operator | Sep 2024 |
| 376 | Matador E & P Company Inc | | Oil & Gas Operator | May 2020 |
| 377 | May Petroleum, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Nov 1998 |
| 378 | McGee, Tom Corporation | Booker, TX 79005 | Oil & Gas Operator | Sep 2024 |
| 379 | McOr Oil & Gas Corp | Houston, TX 77002 | Oil & Gas Operator | Oct 2013 |
| 380 | Meade Energy Corporation | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | Oct 2024 |
| 381 | Meadowbrook Oil Corporation Of Ok Inc | Del City, OK 73115-3608 | Oil & Gas Operator | Oct 2024 |
| 382 | Medallion Petroleum, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2015 |
| 383 | Medicine Bow Operating Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2014 |
| 384 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Dec 2024 |
| 385 | Mesa Operating LP | Irving, TX 75039-3746 | Oil & Gas Operator | Oct 2010 |
| 386 | Metropolitan Resources Corp | Tulsa, OK 74169-1734 | Oil & Gas Operator | Mar 2015 |
| 387 | Mewbourne Marketing Inc | Tyler, TX 75711 | Oil & Gas Operator | Mar 2013 |
| 388 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | Dec 2024 |
| 389 | Mge Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Sep 2024 |
| 390 | Mid-Continent Petroleum Corp | | Oil & Gas Operator | Mar 2017 |
| 391 | Midgard Energy Company | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 392 | Midway Operating Company, L.L.C. | Woodward, OK 73802 | Oil & Gas Operator | Dec 2024 |
| 393 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 394 | Milmac Operating Company | Lubbock, TX 79408-2976 | Oil & Gas Operator | Sep 2004 |
| 395 | Mito Resources LLC | Edmond, OK 73013 | Oil & Gas Operator | Oct 2024 |
| 396 | Monterey Production Company LLC | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2024 |
| 397 | Moss Ted A Operating Company | Oklahoma City, OK 73126-0187 | Oil & Gas Operator | Jun 1997 |
| 398 | Moss William Properties Inc | Dallas, TX 75219 | Oil & Gas Operator | Apr 2014 |
| 399 | Mountain Front Pipeline Co Inc | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 400 | Muras Energy, Inc. | Edmond, OK 73013 | Oil & Gas Operator | Oct 2024 |