| 601 | Miller, M. M. & Sons | Alice, TX 78333 | Oil & Gas Operator | Apr 2007 |
| 602 | Miller, Mike | Corsicana, TX 75110 | Oil & Gas Operator | Dec 2025 |
| 603 | Miller, Mike / Miller Prod. Co. | Corsicana, TX 75110 | Oil & Gas Operator | Dec 2025 |
| 604 | Miller, R. A. Energy, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2003 |
| 605 | Miller, Rex M. | Putnam, TX 76469 | Oil & Gas Operator | Sep 2022 |
| 606 | Miller, W. C. Operating Company | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2025 |
| 607 | Mills Oil & Gas | Jacksboro, TX 76458 | Oil & Gas Operator | Mar 2008 |
| 608 | Mills, H. E. | Lipan, TX 76462 | Oil & Gas Operator | Sep 2004 |
| 609 | Mills, Jay | Stephenville, TX 76401 | Gas Operator | Apr 2022 |
| 610 | Mills, Pete | Midland, TX 79707 | Oil & Gas Operator | Sep 2005 |
| 611 | Millwee Oil, Inc. | Midland, TX 79705 | Oil & Gas Operator | Dec 2025 |
| 612 | Millwee, John F. | Midland, TX 79705 | Oil & Gas Operator | Jul 2018 |
| 613 | Milo-Austintatious | Houston, TX 77005 | Oil & Gas Operator | Aug 2006 |
| 614 | Miltex Oil Company | Boerne, TX 78006 | Oil & Gas Operator | Dec 2025 |
| 615 | Milton Oil & Gas Company | Charleston, WV 25322 | Gas Operator | Nov 1997 |
| 616 | Miltuck Operating, Inc. | Elysian Field, TX 75642 | Oil & Gas Operator | Dec 1996 |
| 617 | Mims, William S. | Pleasanton, TX 78064 | Oil Operator | Jun 2009 |
| 618 | Min-Tex Oil Corporation | Tulsa, OK 74170 | Oil & Gas Operator | Dec 1996 |
| 619 | Mina Energy, Inc. | Boerne, TX 78006 | Oil & Gas Operator | Feb 2012 |
| 620 | Minco Oil And Gas Co. | Pampa, TX 79066 | Oil & Gas Operator | Aug 2024 |
| 621 | Miner, R. C. Inc. | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Apr 2002 |
| 622 | Miner, R. C. Oil, Inc. | MC Queeney, TX 78123 | Oil & Gas Operator | Dec 2025 |
| 623 | Mineral Development, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1996 |
| 624 | Mineral Resources, Incorporated | Lewisville, TX 75029 | Oil & Gas Operator | Dec 2025 |
| 625 | Mineral Technologies, Inc. | Midland, TX 79704 | Oil & Gas Operator | Dec 2025 |
| 626 | Minexprod LLC | Katy, TX 77494 | Oil Operator | Dec 2025 |
| 627 | Mingus Oil & Gas | Mingus, TX 76463 | Oil & Gas Operator | Dec 2025 |
| 628 | Minihan Oil & Gas Corporation | Midland, TX 79704 | Oil & Gas Operator | Apr 2004 |
| 629 | Minihan Oil & Gas LTD. | Denver, CO 80202 | Oil & Gas Operator | Jul 2006 |
| 630 | Mink, Jay, Oil Co. | Electra, TX 76360 | Oil & Gas Operator | Aug 2017 |
| 631 | Minton Oil & Gas Properties | Graford, TX 76449 | Gas Operator | Dec 2025 |
| 632 | Minuja Oil And Gas LLC | Corpus Christi, TX 78401 | Oil & Gas Operator | Sep 1996 |
| 633 | Minute Hand LLC | Brenham, TX 77834 | Oil & Gas Operator | Dec 2025 |
| 634 | Minuteman Energy, LLC | Georgetown, TX 78633 | Oil & Gas Operator | Feb 2015 |
| 635 | Minyak Producing Company, Inc. | Sabine Pass, TX 77655 | Oil & Gas Operator | Dec 2025 |
| 636 | Miocene Oil & Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Jul 1998 |
| 637 | Miocene Oil & Gas, LTD. | Englewood, CO 80110 | Oil & Gas Operator | Dec 2025 |
| 638 | Mir-Tex Energy Corp. | Mirando City, TX 78369 | Oil & Gas Operator | Aug 2003 |
| 639 | Miramar Petroleum, Inc. | Corpus Chrsti, TX 78463 | Oil & Gas Operator | Sep 2017 |
| 640 | Miranda Energy Corporation | Midland, TX 79705 | Oil & Gas Operator | Jun 2016 |
| 641 | Mirando Crude Oil Co. | Luling, TX 78648 | Oil & Gas Operator | Jul 1994 |
| 642 | Mirando Resource, L.L.C. | Freer, TX 78357 | Oil & Gas Operator | Dec 2025 |
| 643 | Miresco, Inc. | Houston, TX 77060 | Oil & Gas Operator | Jan 1995 |
| 644 | Misener Operating, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Feb 2010 |
| 645 | Mission Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 646 | Mission Exploration, Inc. | Fate, TX 75132 | Oil & Gas Operator | Dec 1987 |
| 647 | Mission Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 648 | Mission River Systems, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Dec 2025 |
| 649 | Mississippi Ventures, Inc. | Granbury, TX 76048 | Gas Operator | Jul 1997 |
| 650 | Mist Prod. & Exploration Corp. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 651 | Mistex Operating, Inc. | Lewisville, TX 75029 | Oil & Gas Operator | Dec 2025 |
| 652 | Mitchell Drilling Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Nov 2000 |
| 653 | Mitchell Ehrlich Oil & Gas, LLC | Austin, TX 78746 | Oil & Gas Operator | Dec 2025 |
| 654 | Mitchell Energy Company L.P. | Spring, TX 77387 | Oil & Gas Operator | Mar 2008 |
| 655 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 656 | Mitchell Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Nov 2000 |
| 657 | Mitchell Resources, Inc. | Addison, TX 75001 | Oil & Gas Operator | Aug 2003 |
| 658 | Mitchell, James - Operator | Lamesa, TX 79331 | Oil & Gas Operator | Mar 2008 |
| 659 | Mito Resources TX LLC | Edmond, OK 73013 | Oil & Gas Operator | Dec 2025 |
| 660 | Mitsui E&P USA LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 661 | Mixon, Robert N. | Lometa, TX 76853 | Oil & Gas Operator | Dec 2025 |
| 662 | MJ Energy Company, LLC | Kilgore, TX 75663 | Oil Operator | Dec 2025 |
| 663 | MJ Oil, Inc. | Houston, TX 77265 | Oil & Gas Operator | Dec 2025 |
| 664 | MJB Oil Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Dec 2025 |
| 665 | MJB Production Company, Inc. | Brownfield, TX 79316 | Oil & Gas Operator | Dec 2025 |
| 666 | MJM Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 667 | MK Operating Co. | Pampa, TX 79065 | Oil & Gas Operator | Jun 2014 |
| 668 | MK Operating Company LLC | Cedar Park, TX 78613 | Oil & Gas Operator | Dec 2025 |
| 669 | MKS Consulting Corporation | Weatherford, TX 76086 | Oil & Gas Operator | Jul 2005 |
| 670 | MKS Natural Gas Company | Weatherford, TX 76086 | Oil & Gas Operator | Mar 2016 |
| 671 | ML Resources, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 672 | MLB Operating Services, LLC | Tenn Colony, TX 75861 | Oil & Gas Operator | Dec 2025 |
| 673 | MLC Co., Inc. | Dallas, TX 75201 | Oil & Gas Operator | Dec 1996 |
| 674 | MLC Operating, LP | Houston, TX 77063 | Oil & Gas Operator | Dec 2025 |
| 675 | MLF, Inc. | Houston, TX 77096 | Gas Operator | Nov 2009 |
| 676 | MM China Star Oil Co., LLC | Woodway, TX 76712 | Oil & Gas Operator | Dec 2025 |
| 677 | MMD Oil Co. | Olney, TX 76374 | Oil & Gas Operator | Dec 2000 |
| 678 | MMG Oil Company | Buffalo Gap, TX 79508 | Oil & Gas Operator | Aug 2006 |
| 679 | MMGL East Texas II, LLC | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 680 | MMGL East Texas III, LLC | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 681 | MMGL TXPH, LLC | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 682 | Mna Enterprises LTD. Co. | Hobbs, NM 88242 | Oil & Gas Operator | Aug 2025 |
| 683 | Mo-Jon, Inc. | Edroy, TX 78352 | Oil & Gas Operator | May 1999 |
| 684 | Mobeetie Resource Dev LLC | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 685 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 2007 |
| 686 | Mobil Petro Vac, Inc. | Duncan, OK 73533 | Oil & Gas Operator | Dec 2025 |
| 687 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Dec 2025 |
| 688 | Mobile Petrovac, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2025 |
| 689 | Mobile Production Systems, Inc. | Austin, TX 78711 | Oil & Gas Operator | Feb 1995 |
| 690 | Mobpar, Inc. | Houston, TX 77219 | Oil & Gas Operator | Dec 2025 |
| 691 | Mockingbird Oil, Inc. (I) | Spring, TX 77389 | Oil & Gas Operator | Dec 2025 |
| 692 | Modena Operating LLC | Houston, TX 77057 | Oil & Gas Operator | Dec 2025 |
| 693 | Modern Exploration, Inc. | Sherman, TX 75090 | Oil & Gas Operator | Dec 2025 |
| 694 | Moenning, Vernie | Electra, TX 76360 | Oil & Gas Operator | Dec 2025 |
| 695 | Mog Energy LLC | Tyler, TX 75701 | Oil Operator | Dec 2025 |
| 696 | Mogul Energy International, Inc. | Houston, TX 77042 | Oil & Gas Operator | Oct 2017 |
| 697 | Mogul Operating LLC | St Petersburg, FL 33706 | Oil Operator | Dec 2025 |
| 698 | Mogul Resources, LLC | Cisco, TX 76437 | Oil & Gas Operator | Dec 2025 |
| 699 | Mohican Exploration, LLC | Graham, TX 76450 | Oil & Gas Operator | Oct 2024 |
| 700 | Mohican Oil & Gas, L.L.C. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Apr 2013 |