| 401 | Landers & Musgrove | Okemah, OK 74859 | Oil & Gas Operator | Mar 2015 |
| 402 | Landers & Musgrove Oil Co. Inc | Okemah, OK 74859-0266 | Oil & Gas Operator | Jan 2018 |
| 403 | Landers & Waldman Inc | Okemah, OK 74859-0660 | Oil & Gas Operator | May 2013 |
| 404 | Landers Oil & Gas Inc | Tulsa, OK 74132-2171 | Oil & Gas Operator | Jan 2025 |
| 405 | Lar-Mie Petroleum Inc | Tulsa, OK 74136 | Oil & Gas Operator | Aug 1998 |
| 406 | Larkspur Operating LLC | Oklahoma City, OK 73034 | Oil & Gas Operator | Jan 2025 |
| 407 | Larry Sherman Oil LLC | Chandler, OK 74834 | Oil & Gas Operator | Jan 2025 |
| 408 | Larry Wolff Dba Wolff'S Oilfield Service | Cushing, OK 74023-9789 | Oil & Gas Operator | Feb 2025 |
| 409 | Las Colinas Oil Corp. | Irving, TX 75062 | Oil & Gas Operator | Mar 2015 |
| 410 | Laurel Operating Company, Inc. | Stillwater, OK 74074-3025 | Oil & Gas Operator | Jan 2025 |
| 411 | Lawrence James LLC | Guthrie, OK 73044-9622 | Oil & Gas Operator | Feb 2025 |
| 412 | Lazy H Investment | Chandler, OK 74834 | Oil & Gas Operator | Nov 1993 |
| 413 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 414 | Leasehold Management Corp | Oklahoma City, OK 73170 | Oil & Gas Operator | Nov 2024 |
| 415 | Leavell Resources Corporation | Hays, KS 67601 | Oil & Gas Operator | Mar 2015 |
| 416 | Legacy - M & K Corporation | Dallas, TX 75231-0969 | Oil & Gas Operator | Jan 2025 |
| 417 | Lewis Oil Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Jan 2025 |
| 418 | Lewis, R. J. Oil Company | Stillwater, OK 74076 | Oil & Gas Operator | Apr 2014 |
| 419 | Lincoln Tank Truck Service Inc | Stroud, OK 74079-0662 | Oil & Gas Operator | May 2013 |
| 420 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Aug 2024 |
| 421 | Little River Energy Company | Drumright, OK 74030 | Oil & Gas Operator | Feb 2025 |
| 422 | Little Thunder, LLC | Bartlesville, OK 74003 | Oil Operator | Jan 2025 |
| 423 | Lobar Oil Co LLC | Oklahoma City, OK 73116-1516 | Oil & Gas Operator | Jan 2025 |
| 424 | Lord Enterprises Inc | Oklahoma City, OK 73106-5050 | Oil & Gas Operator | Sep 2000 |
| 425 | Lre Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Nov 2016 |
| 426 | Lu-Ray Petroleum LLC | Oklahoma City, OK 73121-1607 | Oil & Gas Operator | Feb 2025 |
| 427 | Lunar Investments Inc | Oklahoma City, OK 73118-4823 | Oil & Gas Operator | Jan 2025 |
| 428 | Luther Oil Inc | Cameron Park, CA 95682-8865 | Oil & Gas Operator | Apr 2020 |
| 429 | Luween Energy LLC | Palisade, CO 81526 | Oil & Gas Operator | Jan 2025 |
| 430 | M C L Company LTD | Edmond, OK 73083-6243 | Oil & Gas Operator | Jul 2001 |
| 431 | M C Oil | Tryon, OK 74875 | Oil Operator | Jul 1993 |
| 432 | M E Klein & Associates LLC | Washington, OK 73093-4663 | Oil & Gas Operator | Feb 2025 |
| 433 | M G Energy LLC | Cushing, OK 74023 | Oil Operator | Jan 2025 |
| 434 | M M Resources, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Sep 2018 |
| 435 | Mac Engineering & Operating Co | | Oil & Gas Operator | May 2005 |
| 436 | Mack Energy Co. | Duncan, OK 73534 | Oil & Gas Operator | Feb 2025 |
| 437 | Mackellar Inc | Oklahoma City, OK 73116-7101 | Oil & Gas Operator | Feb 2025 |
| 438 | Magaw & Zimmer | Perry, OK 73077-1055 | Oil & Gas Operator | Aug 2013 |
| 439 | Maggard Oil Co Inc | Manford, OK 74044 | Oil & Gas Operator | Sep 1997 |
| 440 | Maggard Supply & Oil Company | Mannford, OK 74044-1407 | Oil & Gas Operator | Nov 2014 |
| 441 | Magma Resources LLC | Paoli, OK 73074 | Oil & Gas Operator | Jan 2025 |
| 442 | Magnum Energy Inc | Norman, OK 73072-2403 | Oil & Gas Operator | Feb 2025 |
| 443 | Maguire James Q Inc | Norman, OK 73070-1748 | Oil & Gas Operator | Jun 2011 |
| 444 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 445 | Manna Corporation | Oklahoma City, OK 73162 | Oil & Gas Operator | Dec 2014 |
| 446 | Mantex Inc | Tulsa, OK 74114-6234 | Oil & Gas Operator | Mar 2015 |
| 447 | Manuel Corporation | Wichita, KS 67206 | Oil & Gas Operator | Jan 2025 |
| 448 | Maple Properties Corp | Dallas, TX 75204 | Oil & Gas Operator | Jan 1999 |
| 449 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Feb 2025 |
| 450 | Marbet LLC | Edmond, OK 73013-6691 | Oil & Gas Operator | Jan 2025 |
| 451 | Marjo Operating Company Inc | Tulsa, OK 741010729 | Oil & Gas Operator | Jan 2025 |
| 452 | Marjo Operating Mid-Continent LLC | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 453 | Marshall Oil Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Apr 2017 |
| 454 | Martin John R | Cushing, OK 74023 | Oil & Gas Operator | Apr 1995 |
| 455 | Martin Tank Truck & Casing Pulling Inc | Cushing, OK 74023 | Oil & Gas Operator | Apr 2015 |
| 456 | Masham Production Corporation | Enid, OK 73702 | Oil & Gas Operator | Aug 2000 |
| 457 | Mason Robert A | | Oil Operator | May 1993 |
| 458 | Mason Robert A Production Co | Edmond, OK 73013-9102 | Oil & Gas Operator | May 2013 |
| 459 | Mattea Oil & Gas LLC | Drumright, OK 74023 | Oil & Gas Operator | Nov 2024 |
| 460 | May Energy Company | Stroud, OK 74079 | Oil & Gas Operator | May 2013 |
| 461 | Mayfield Engineering Service | Tulsa, OK 74104 | Oil & Gas Operator | Apr 2025 |
| 462 | McCool John E | Youngsville, PA 16371 | Oil & Gas Operator | Jan 2025 |
| 463 | McCord Al Inc | Norman, OK 73072-6720 | Oil & Gas Operator | Feb 2011 |
| 464 | McFerran Operating LLC | Seminole, OK 74868-6202 | Oil & Gas Operator | Jan 2025 |
| 465 | McGriff Craig Exploration Inc | Oklahoma City, OK 73172-0364 | Oil & Gas Operator | Mar 2023 |
| 466 | McQueen Ed & Company Inc | Lindsey, OK 73052 | Oil & Gas Operator | Apr 2014 |
| 467 | Meade Energy Corporation | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | Feb 2025 |
| 468 | Meadowbrook Oil Corporation Of Ok Inc | Del City, OK 73115-3608 | Oil & Gas Operator | Feb 2025 |
| 469 | Meason Petroleum LLC | Tulsa, OK 74119-3026 | Oil & Gas Operator | Dec 2016 |
| 470 | Mega Resources Inc | Dallas, TX 75225-0186 | Oil & Gas Operator | Jan 2001 |
| 471 | Mel-Ray Oil Company | Nowata, OK 74048-0149 | Oil & Gas Operator | Mar 2004 |
| 472 | Mesa Exploration Company Inc | Shawnee, OK 74801 | Oil & Gas Operator | Jan 2025 |
| 473 | Michael Goodnight Operating LLC | St Louis, OK 74866 | Oil & Gas Operator | Jan 2025 |
| 474 | Mickalson Operating Company | Cleveland, OK 74020 | Oil & Gas Operator | Feb 2025 |
| 475 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Feb 2025 |
| 476 | Mid-Con Gas Corp | Yukon, OK 73099 | Oil & Gas Operator | Feb 2014 |
| 477 | Mid-Continent Energy Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 478 | Mid-Continent Petroleum Corp | | Oil & Gas Operator | Mar 2017 |
| 479 | Mid-Way Environmental Services Inc | Stroud, OK 74079 | Oil Operator | Feb 2022 |
| 480 | Middle Bay Production Co. Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2014 |
| 481 | Miller Exploration Company | Tulsa, OK 74136-1020 | Oil & Gas Operator | Mar 2015 |
| 482 | Miller John Production | Bristow, OK 74010-2455 | Oil & Gas Operator | Jul 2016 |
| 483 | Miller-McGee Operating Inc | Stroud, OK 74079 | Oil & Gas Operator | Jan 2025 |
| 484 | Milmac Operating Company | Lubbock, TX 79408-2976 | Oil & Gas Operator | Sep 2004 |
| 485 | Miner Rick | Drumright, OK 74030-0373 | Oil & Gas Operator | Jan 2025 |
| 486 | Miner Rick Oil Inc | Drumright, OK 74030-0373 | Oil & Gas Operator | Apr 2022 |
| 487 | Minihan Oil And Gas Company | Seminole, OK 74868-9790 | Oil & Gas Operator | Sep 2014 |
| 488 | Mission Leasing LTD | Tulsa, OK 74136 | Oil Operator | Dec 2000 |
| 489 | Montclair Energy LLC | Edmond, OK 73034-7291 | Oil & Gas Operator | Jan 2025 |
| 490 | Moran Oil Enterprises, LLC | Seminole, OK 74818 | Oil & Gas Operator | Dec 2024 |
| 491 | Moran-K Oil LLC | Seminole, OK 74868 | Oil & Gas Operator | Feb 2025 |
| 492 | Morgan Energy Corporation | Englewood, CO 80110 | Oil & Gas Operator | Mar 2006 |
| 493 | Morrison International Energy Inc | Oklahoma City, OK 73189-0537 | Oil & Gas Operator | Dec 2024 |
| 494 | Morton Drilling Company | Bristow, OK 74010-1279 | Oil & Gas Operator | Jun 1995 |
| 495 | Morton Production Inc | Ada, OK 74820-2643 | Oil & Gas Operator | Sep 2014 |
| 496 | Moss Ted A Operating Company | Oklahoma City, OK 73126-0187 | Oil & Gas Operator | Jun 1997 |
| 497 | MT Energy LLC | Waskom, TX 75692 | Oil & Gas Operator | Apr 2025 |
| 498 | Multistates Oil Properties, NV | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 1998 |
| 499 | Musgrove, Casey Oil | Ponca City, OK 74602-0391 | Oil & Gas Operator | Jun 2017 |
| 500 | Myjo Oil Corporation | Breckenridge, TX 76024 | Oil Operator | Jul 1996 |