| 301 | Ham Oil Company, LLC | | Oil Operator | Sep 2022 |
| 302 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 303 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 304 | Hays Production LLC | Velma, OK 73491 | Oil & Gas Operator | Feb 2025 |
| 305 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Jan 2025 |
| 306 | Henderson Fred J | Okmulgee, OK 74447-9204 | Oil & Gas Operator | Jan 2025 |
| 307 | Henry Petroleum Of Oklahoma LP | Midland, TX 79703-5000 | Oil & Gas Operator | Feb 2017 |
| 308 | Hep Oil Company LTD | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2012 |
| 309 | Hep Oil GP, LLC | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 310 | Hibbert R E Estate Of | Houston, TX 77002-3211 | Oil & Gas Operator | Apr 2015 |
| 311 | High Sierra Crude Oil& Marketing LLC | Ardmore, OK 73401 | Oil Operator | Nov 2013 |
| 312 | Highland Energy Co | Dallas, TX 75201 | Oil & Gas Operator | Jun 1994 |
| 313 | Hikcott Oil | Wilson, OK 73463-6537 | Oil Operator | Jan 2014 |
| 314 | HMD Oil Co Inc | Ardmore, OK 73401-2542 | Oil & Gas Operator | Feb 2025 |
| 315 | Hoard John L Family Trust | Ardmore, OK 73402-1706 | Oil & Gas Operator | Jun 2022 |
| 316 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | Feb 2025 |
| 317 | Holden Energy Corporation | Ardmore, OK 73401 | Oil & Gas Operator | Mar 2015 |
| 318 | Hondo Oil & Gas Company | Roswell, NM 88202 | Oil & Gas Operator | Aug 2006 |
| 319 | Hooks Dwain | Tatums, OK 73487 | Oil & Gas Operator | Oct 2024 |
| 320 | Horton Mary | Ratliff City, OK 73481 | Oil Operator | May 2020 |
| 321 | HRB Operating Company Inc | Bridgeport, TX 76426 | Oil & Gas Operator | Apr 2025 |
| 322 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Apr 2025 |
| 323 | Huck Farms LLC | Stratford, OK 74872 | Oil & Gas Operator | Jan 2025 |
| 324 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 325 | Hunton Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Feb 2025 |
| 326 | Hyperion Energy LP | Dallas, TX 75206 | Oil & Gas Operator | May 2014 |
| 327 | Indian Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | Apr 2025 |
| 328 | Injection Well Service | Lone Grove, OK 73443-0156 | Oil Operator | Apr 2005 |
| 329 | J & E Energy Company | Oklahoma City, OK 73120-1108 | Oil & Gas Operator | Mar 2015 |
| 330 | J & J Oil Company LLC | Lubbock, TX 79424 | Oil Operator | Apr 2025 |
| 331 | J & K Operating Co LLC | Delaware, OK 74027 | Oil & Gas Operator | Feb 2024 |
| 332 | J & K Production LLC | Konawa, OK 74849 | Oil Operator | Feb 2025 |
| 333 | J & L Oil Company | El Dorado, AR 71730 | Oil Operator | Jan 2025 |
| 334 | J D Sutton Inc | Loco, OK 73442-9701 | Oil & Gas Operator | Feb 2025 |
| 335 | Jackson Emma Trust | Duncan, OK 73534-1388 | Oil & Gas Operator | Oct 2016 |
| 336 | Jaycar Production LLC | Comanche, OK 73529-4670 | Oil Operator | Feb 2025 |
| 337 | Jhatco Inc | Enid, OK 73701 | Oil & Gas Operator | Feb 2025 |
| 338 | Jimmy R Chatham LLC | Healdton, OK 73438 | Oil & Gas Operator | Feb 2025 |
| 339 | Jma Energy Company LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2025 |
| 340 | Johnson E Lyle | Oklahoma City, OK 73142 | Oil & Gas Operator | Jan 2025 |
| 341 | Johnson Oil Company | Duncan, OK 73533 | Oil Operator | Feb 2025 |
| 342 | Jolen Operating Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2025 |
| 343 | Jones & Pellow Oil Co | Oklahoma City, OK 73118-1115 | Oil & Gas Operator | Feb 2015 |
| 344 | Jones Energy LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Jan 2025 |
| 345 | Jones III Thomas J | Duncan, OK 73533-4995 | Oil & Gas Operator | Dec 2018 |
| 346 | Jones Oil Company | Ardmore, OK 73402-1389 | Oil & Gas Operator | Aug 2022 |
| 347 | Jones Oil Company LLC (The) | Duncan, OK 73533-4995 | Oil & Gas Operator | Jan 2025 |
| 348 | Jones, L. E. Production Co. | Duncan, OK 73534 | Oil & Gas Operator | Jul 2014 |
| 349 | K L Production Services LLC | Duncan, OK 73533-3409 | Oil & Gas Operator | Nov 2019 |
| 350 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Apr 2025 |
| 351 | Kantor Oil Company, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2025 |
| 352 | Kate F H | Oklahoma City, OK 73122 | Oil & Gas Operator | Jun 2000 |
| 353 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Jan 2025 |
| 354 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 355 | Keith F. Walker Oil & Gas Co., LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2025 |
| 356 | Kepco Operating, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2024 |
| 357 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 358 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Jan 2025 |
| 359 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Apr 2025 |
| 360 | Kerr-McGee Refining Corp | Oklahoma City, OK 73125 | Oil & Gas Operator | Jun 2007 |
| 361 | Kiamichi Resources Inc | Oklahoma City, OK 73143 | Oil & Gas Operator | Feb 2016 |
| 362 | Kiester Operating Company | Oklahoma City, OK 73106 | Oil & Gas Operator | Jan 2025 |
| 363 | Kimball Production Co. | Houston, TX 77042 | Oil & Gas Operator | Jul 2002 |
| 364 | King Energy LLC | Oklahoma City, OK 73116-9044 | Oil & Gas Operator | Feb 2025 |
| 365 | Kingery Drilling Co., Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Jan 2025 |
| 366 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Apr 2025 |
| 367 | Kirkpatrick Ronald B | | Oil & Gas Operator | Jul 2013 |
| 368 | KLBW Partners LLC | Ratliff City, OK 73481 | Oil & Gas Operator | Feb 2025 |
| 369 | Klo LLC | Tulsa, OK 74120-2428 | Oil & Gas Operator | Feb 2025 |
| 370 | Knutson Production Company | Loco, OK 73442-9706 | Oil & Gas Operator | Feb 2025 |
| 371 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 372 | Kodiak Oil & Gas Inc | Muenster, TX 76252 | Oil & Gas Operator | Apr 2025 |
| 373 | Kolibri Energy Us, Inc. | Thousand Oaks, CA 91320-1272 | Oil & Gas Operator | Feb 2025 |
| 374 | KWB Oil Property Management Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2025 |
| 375 | L & B Oil Company Inc | Houston, TX 77019-3115 | Oil & Gas Operator | Jan 2025 |
| 376 | L & F Oil Company | Duncan, OK 73533-3636 | Oil Operator | Jun 2009 |
| 377 | L & T Disposal LLC | Wilson, OK 73463-6545 | Oil Operator | Mar 2016 |
| 378 | L E Jones Operating Inc | Duncan, OK 73534 | Oil & Gas Operator | Feb 2025 |
| 379 | Lake Country Disposal II LLC | Wilson, OK 73463 | Oil Operator | Jan 2025 |
| 380 | Lake Country Disposal LLC | Ardmore, OK 73401 | Oil Operator | Oct 2024 |
| 381 | Lamamco Drilling Company | Skiatook, OK 74070 | Oil & Gas Operator | Jan 2025 |
| 382 | Lambert Company LLC | Healdton, OK 73438-0962 | Oil & Gas Operator | Jan 2025 |
| 383 | Lambert Company The | Healdton, OK 73438-0962 | Oil & Gas Operator | Feb 2023 |
| 384 | Lamima Corporation | Ardmore, OK 73401 | Oil Operator | Nov 1994 |
| 385 | Lance Ruffel Oil & Gas LLC | Oklahoma City, OK 73102-5632 | Oil & Gas Operator | Feb 2025 |
| 386 | Langley Harold | Graham, OK 73437 | Oil Operator | Jan 2025 |
| 387 | Lariat Petroleum Inc | Tulsa, OK 74119 | Oil & Gas Operator | Sep 2024 |
| 388 | Larson Exploration Company | Tulsa, OK 74136-4939 | Oil & Gas Operator | Jul 2016 |
| 389 | Lavrco Energie Inc | Duncan, OK 73533 | Oil & Gas Operator | Oct 2024 |
| 390 | Lawrence Hot Oil Service | Loco, OK 73442 | Oil & Gas Operator | Feb 2025 |
| 391 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 392 | Le Norman Partners LLC | Duncan, OK 73533-9523 | Oil & Gas Operator | Feb 2012 |
| 393 | Leg Up Operating Company LLC | Tulsa, OK 74135 | Oil Operator | Jan 2025 |
| 394 | Lemley Oil Corporation | Sulphur, OK 73086-9316 | Oil & Gas Operator | Jan 2025 |
| 395 | Leonard Brothers Operating Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Apr 2025 |
| 396 | Lewis J K | Duncan, OK 73534-1742 | Oil & Gas Operator | Apr 2015 |
| 397 | Lewis James D Oil Company | Healdton, OK 73438 | Oil Operator | Jan 2025 |
| 398 | Lewis Oil Operations LLC | Ratliff City, OK 73481 | Oil & Gas Operator | Jan 2025 |
| 399 | Lime Rock Resources A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Jan 2025 |
| 400 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Jan 2025 |