| 501 | Legacy Energy Services LLC | | Oil & Gas Operator | Jan 2024 |
| 502 | Legacy Reserves Operating LP | Denver, CO 80202 | Oil & Gas Operator | Apr 2024 |
| 503 | Lewbet Inc | Perry, OK 73077-8914 | Oil & Gas Operator | Jan 2024 |
| 504 | Likins-Foster Honolulu Corp | Foster City, CA 94404 | Oil & Gas Operator | Feb 2015 |
| 505 | Limestone Exploration II, LLC | Midland, TX 79704 | Oil & Gas Operator | Jun 2019 |
| 506 | Limestone Productions | Bartlesville, OK 74006-8229 | Oil & Gas Operator | Sep 2013 |
| 507 | Lincoln Ventures LLC | | Oil & Gas Operator | Jan 2024 |
| 508 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Feb 2024 |
| 509 | Little Bear Resources LLC | Stillwater, OK 74074-1388 | Oil & Gas Operator | Feb 2013 |
| 510 | Little River Energy Co. | Drumright, OK 74030 | Oil & Gas Operator | Jan 2024 |
| 511 | Littrell Chemical Inc | Cleo Springs, OK 73729 | Oil & Gas Operator | Jan 2005 |
| 512 | Litzenberger Exploration Inc | Waynoka, OK 73860-0217 | Oil & Gas Operator | Feb 2024 |
| 513 | Longacre Oil & Gas | Enid, OK 73702 | Oil & Gas Operator | Mar 2013 |
| 514 | Longfellow Energy, LP | Dallas, TX 75225 | Oil & Gas Operator | Apr 2024 |
| 515 | Lorentz Oil & Gas LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Feb 2024 |
| 516 | Louis Dreyfus Gas Marketing | Oklahoma City, OK 73134 | Oil & Gas Operator | Mar 2018 |
| 517 | Lu-Ray Petroleum LLC | Oklahoma City, OK 73121-1607 | Oil & Gas Operator | Feb 2024 |
| 518 | LX4 LLC | | Oil Operator | Jan 2024 |
| 519 | M & D Pumping Service Inc | Ringwood, OK 73768-3415 | Oil & Gas Operator | Feb 2024 |
| 520 | M And V Resources Inc | Crescent, OK 73028-0772 | Oil & Gas Operator | Feb 2024 |
| 521 | M E Klein & Associates LLC | Washington, OK 73070-8106 | Oil & Gas Operator | Feb 2024 |
| 522 | M H Oil & Gas LLC | Okeene, OK 73763-0684 | Oil & Gas Operator | Feb 2024 |
| 523 | M M Energy, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Jan 2024 |
| 524 | M M Resources, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Sep 2018 |
| 525 | Mac Laskey Kelly Oilfield | El Dorado, KS 67042 | Oil & Gas Operator | Feb 2024 |
| 526 | Mack Energy Co. | Duncan, OK 73534 | Oil & Gas Operator | Feb 2024 |
| 527 | Mack Oil Company | Duncan, OK 73534 | Oil & Gas Operator | Nov 2000 |
| 528 | Mackellar Inc | Oklahoma City, OK 73154-0298 | Oil & Gas Operator | Feb 2024 |
| 529 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 530 | Malvern Group Inc | Clearwater, FL 33758-6817-6817 | Oil & Gas Operator | Mar 2005 |
| 531 | Manuel Corporation | Wichita, KS 67206 | Oil & Gas Operator | Jan 2024 |
| 532 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Feb 2024 |
| 533 | Marbet LLC | Edmond, OK 73013-6691 | Oil & Gas Operator | Jan 2024 |
| 534 | Marjo Operating Company Inc | Tulsa, OK 741010729 | Oil & Gas Operator | Jan 2024 |
| 535 | Marjo Operating Mid-Continent LLC | | Oil & Gas Operator | Feb 2024 |
| 536 | Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Jan 2024 |
| 537 | Massad George H Estate | Holdenville, OK 74848 | Oil & Gas Operator | Dec 2014 |
| 538 | Massad Oil Company | Holdenville, OK 74848-2629 | Oil Operator | Feb 2024 |
| 539 | Maverick Brothers Resources LLC | Enid, OK 73702-0392 | Oil & Gas Operator | Jan 2024 |
| 540 | Maxim Energy Corporation | Baytown, TX 77520 | Oil & Gas Operator | Jan 2024 |
| 541 | Maxwell Resources Corporation | Oklahoma City, OK 73116-7746 | Oil & Gas Operator | Apr 2009 |
| 542 | Mayabb Oil Company Inc | Tulsa, OK 74105-5158 | Oil & Gas Operator | Jan 2024 |
| 543 | McCoy Alex W & Associates | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2009 |
| 544 | McDe Energy Company Inc | Enid, OK 73706 | Oil & Gas Operator | May 2009 |
| 545 | McKay Oil Company | Perry, OK 73077 | Oil Operator | Nov 2008 |
| 546 | McMillin C C & Company Inc | Guthrie, OK 73044-0546 | Oil & Gas Operator | Jan 2024 |
| 547 | McO Resources Integrated Corp | Houston, TX 77057 | Oil Operator | Jan 1997 |
| 548 | McQueen Ed & Company Inc | Lindsey, OK 73052 | Oil & Gas Operator | Apr 2014 |
| 549 | Meadowbrook Oil Corporation Of Ok Inc | Del City, OK 73115-3608 | Oil & Gas Operator | Feb 2024 |
| 550 | Medicine Bow Operating Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2014 |
| 551 | Megaenergy Operating, Inc. | Edmond, OK 73034 | Oil & Gas Operator | Jul 2015 |
| 552 | Melzer Exploration Company | Midland, TX 79702-2083 | Oil & Gas Operator | May 2013 |
| 553 | Mendell Petroleum Corporation | Castle Rock, CO 80104-9045 | Oil & Gas Operator | Sep 2004 |
| 554 | Mermac Operating Company Inc | Norman, OK 73072 | Oil & Gas Operator | Mar 2015 |
| 555 | Mid-Con Central Expl Co | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2014 |
| 556 | Mid-Con Gas Corp | Yukon, OK 73099 | Oil & Gas Operator | Feb 2014 |
| 557 | Middle Bay Production Co. Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2014 |
| 558 | Midgard Energy Company | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 559 | Midnight Hour LLC | Enid, OK 73702 | Oil & Gas Operator | Apr 2020 |
| 560 | Midstates Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2000 |
| 561 | Midwest Pipe & Supply Company | Oklahoma City, OK 73154-0245 | Oil & Gas Operator | Dec 2008 |
| 562 | Miller Exploration Company | Tulsa, OK 74136-1020 | Oil & Gas Operator | Mar 2015 |
| 563 | Miracle Production Inc | Yukon, OK 73085-0680 | Oil & Gas Operator | Jun 2007 |
| 564 | Mito Resources LLC | Edmond, OK 73013 | Oil & Gas Operator | Feb 2024 |
| 565 | Monroe Natural Gas Inc | Norman, OK 73070-5687 | Oil & Gas Operator | Jan 2024 |
| 566 | Moore & Moore Energy Inc | Purcell, OK 73080-0674 | Oil & Gas Operator | Dec 2012 |
| 567 | Moore Richard L | Morris, OK 74445 | Oil Operator | Aug 2013 |
| 568 | Morgan David E | Enid, OK 73702-3525 | Oil & Gas Operator | Sep 2016 |
| 569 | Mott Petroleum Corporation | Sugar Land, TX 77487-3058 | Oil & Gas Operator | Jan 2024 |
| 570 | MSB Operating Company | Enid, OK 73703 | Oil & Gas Operator | Jan 2005 |
| 571 | MT Dora Energy LLC | Houston, OK 77056-1940 | Oil & Gas Operator | Jun 2019 |
| 572 | MT Energy LLC | Waskom, TX 75692 | Oil & Gas Operator | Apr 2024 |
| 573 | Mud Operations Inc | Ames, OK 73718-9501 | Oil & Gas Operator | Feb 2024 |
| 574 | Muegge Don E | Lamont, OK 74643-5010 | Oil & Gas Operator | Dec 1996 |
| 575 | Muegge, Clay A. | Lamont, OK 74643 | Oil & Gas Operator | Feb 2024 |
| 576 | Muras Energy, Inc. | Edmond, OK 73013 | Oil & Gas Operator | Jan 2024 |
| 577 | Mustang Fuel Corp. Of Oklahoma | Oklahoma City, OK 73106 | Oil & Gas Operator | Nov 2016 |
| 578 | Mustang Fuel Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2024 |
| 579 | Mustang Gas Products LLC | Oklahoma City, OK 73114-7406 | Oil & Gas Operator | Sep 2022 |
| 580 | Nadel And Gussman, L.L.C. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2024 |
| 581 | National Energy Group Inc | Dallas, TX 75206 | Oil & Gas Operator | Sep 2014 |
| 582 | National Oil Company | Garden City, KS 67846 | Oil & Gas Operator | Jan 2024 |
| 583 | Nbi Services, Inc. | Tulsa, OK 74159 | Oil & Gas Operator | Apr 2024 |
| 584 | Neg Operating LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Apr 2017 |
| 585 | Neilson Inc | Nash, OK 73761-5026 | Oil & Gas Operator | Aug 2022 |
| 586 | Nelson Exploration Corporation | | Oil & Gas Operator | Jan 2024 |
| 587 | Nemaha Environmental Services LLC | Enid, OK 73703 | Oil Operator | Feb 2024 |
| 588 | Nerco Oil & Gas, Inc. | | Oil & Gas Operator | Dec 1996 |
| 589 | Nexus Resources Corporation | Drumright, OK 74030 | Oil & Gas Operator | Jan 2013 |
| 590 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Apr 2024 |
| 591 | Noble Energy Production Inc | Houston, TX 77067 | Oil & Gas Operator | Apr 2024 |
| 592 | Nordstrand Engineering Inc | Houston, TX 77019 | Oil & Gas Operator | Apr 2024 |
| 593 | Northbrook Oil & Gas Company | Norman, OK 73070-4916 | Oil & Gas Operator | Jun 2016 |
| 594 | Nytex Energy LLC | Edmond, OK 73083-5946 | Oil & Gas Operator | Sep 2015 |
| 595 | O G & E | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Feb 2014 |
| 596 | O K Swabbing Inc | Hennessey, OK 73742-0835 | Oil & Gas Operator | Jan 2024 |
| 597 | O'Neal Oil & Gas Co | Fort Worth, TX 76107-1479 | Oil & Gas Operator | Feb 2024 |
| 598 | O.G.P. Operating, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Apr 2024 |
| 599 | Oberlander Leslie A Jake | Covington, OK 73730 | Oil Operator | Jun 2007 |
| 600 | Odessa Oil Investment Co., Inc. | Odessa, TX 79762 | Oil & Gas Operator | Nov 2016 |