| 601 | McDaniel, Willard Jr. Oil Co. | Marble Falls, TX 78654 | Oil & Gas Operator | Mar 2005 |
| 602 | McDonald Production | Lubbock, TX 79408 | Oil & Gas Operator | Mar 2003 |
| 603 | McDonald, Richard A. | Fredericksbrg, TX 78624 | Oil & Gas Operator | May 2025 |
| 604 | McFarland & Scobey, Inc. | El Paso, TX 79947 | Oil & Gas Operator | May 2025 |
| 605 | McGuffin, Joe Jr. | Christoval, TX 76935 | Oil & Gas Operator | May 2025 |
| 606 | McLeod, George L. Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2002 |
| 607 | MDC Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Oct 2022 |
| 608 | Meadco Properties | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 609 | Meco IV Holdco, LLC | Lakewood, CO 80227 | Oil & Gas Operator | Jul 2022 |
| 610 | Meco IV, LLC | Lakewood, CO 80227 | Oil & Gas Operator | Jul 2021 |
| 611 | Medallion Exploration Corp. | Midvale, UT 84047 | Oil & Gas Operator | Oct 1998 |
| 612 | Mellon Creek Operating Co. | Victoria, TX 77901 | Oil & Gas Operator | Jun 1993 |
| 613 | Memorial Exploration Company | Saint Louis, MO 63105 | Oil & Gas Operator | Aug 1996 |
| 614 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 615 | Merenco | Midland, TX 79702 | Oil & Gas Operator | Dec 1996 |
| 616 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 617 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 618 | Merrill Operating, LLC | Snyder, TX 79550 | Oil Operator | Apr 2016 |
| 619 | Mescalero Energy, Inc. | San Antonio, TX 78231 | Oil & Gas Operator | Aug 2003 |
| 620 | Mesquite SWD Inc | Carlsbad, NM 88221 | Oil & Gas Operator | May 2025 |
| 621 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | May 2025 |
| 622 | Mexco Energy Corporation | Midland, TX 79702 | Oil & Gas Operator | Feb 2020 |
| 623 | MFP Petroleum LP | Oklahoma City, OK 73142-3017 | Gas Operator | Feb 2025 |
| 624 | MGF Oil Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1998 |
| 625 | Mid-States Operating Company | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 626 | Mid-Tex Energy Inc. | Costa Mesa, CA 92626 | Oil & Gas Operator | Jan 1999 |
| 627 | Midpar L.P. | Midland, TX 79702 | Oil & Gas Operator | Feb 1995 |
| 628 | Millennium Resources, LLC. | Big Lake, TX 76932 | Oil & Gas Operator | Sep 2012 |
| 629 | Millennium Resources, LP | Midland, TX 79708 | Oil Operator | May 2025 |
| 630 | Mills, Pete | Midland, TX 79707 | Oil & Gas Operator | Sep 2005 |
| 631 | Miltex Oil Company | Boerne, TX 78006 | Oil & Gas Operator | May 2025 |
| 632 | Mineral Development, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1996 |
| 633 | Mineral Technologies, Inc. | Midland, TX 79704 | Oil & Gas Operator | May 2025 |
| 634 | Minute Hand LLC | Brenham, TX 77834 | Oil & Gas Operator | May 2025 |
| 635 | MLC Operating, LP | Houston, TX 77063 | Oil & Gas Operator | May 2025 |
| 636 | Mna Enterprises LTD. Co. | Hobbs, NM 88242 | Oil & Gas Operator | May 2025 |
| 637 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 638 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | May 2025 |
| 639 | Molder, Tom | Imperial, TX 79743 | Oil & Gas Operator | May 2025 |
| 640 | Momentum Energy Corporation | Austin, TX 78746 | Oil & Gas Operator | May 2025 |
| 641 | Moncrief W A Jr | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 642 | Mongoose Energy, LLC | San Antonio, TX 78249 | Oil & Gas Operator | May 2025 |
| 643 | Montex Drilling Company LLC | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 644 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 645 | Moonlite Oil & Gas Company | Imperial, TX 79743 | Oil & Gas Operator | May 2025 |
| 646 | Moore & Gilmore | Midland, TX 79701 | Oil & Gas Operator | Oct 2008 |
| 647 | Moriah Resources, Inc. | Midland, TX 79704 | Oil & Gas Operator | Mar 2008 |
| 648 | Morningstar Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 649 | Morningstar Partners, L.P. | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2022 |
| 650 | Morris, W. Dale Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | May 2025 |
| 651 | Mosaic Midland LLC | Dallas, TX 75367 | Oil Operator | May 2025 |
| 652 | Mosaic Oil LLC | Dallas, TX 75205 | Oil & Gas Operator | May 2025 |
| 653 | Mosaic Pecos LLC | Dallas, TX 75367 | Oil Operator | May 2025 |
| 654 | Mosaic Texas LLC | Dallas, TX 75205 | Oil & Gas Operator | May 2025 |
| 655 | Moy, Gary | Falls City, TX 78113 | Oil & Gas Operator | Nov 1998 |
| 656 | Mr Oil Company | Monahans, TX 79756 | Oil & Gas Operator | Nov 2004 |
| 657 | Mulloy Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | May 2025 |
| 658 | Munn, W. H. Operating Company | Midland, TX 79702 | Oil & Gas Operator | Sep 2002 |
| 659 | Munoco Co. | El Dorado, AR 71730 | Oil & Gas Operator | Jul 2021 |
| 660 | Muras Energy Inc | Edmond, OK 73013 | Oil & Gas Operator | Feb 2025 |
| 661 | Murphy Exploration & Prod. Co. | Houston, TX 77094 | Oil & Gas Operator | Jun 2011 |
| 662 | Murphy Oil USA Inc | New Orleans, LA 70161 | Oil & Gas Operator | Jan 1993 |
| 663 | Mustang Oil & Gas Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2021 |
| 664 | MV2 Energy, Inc. | Houston, TX 77069 | Oil & Gas Operator | May 2025 |
| 665 | MZ Operating, Inc | Midland, TX 79701 | Oil & Gas Operator | Apr 1994 |
| 666 | N & B Oil And Gas LLC | Monahans, TX 79756 | Oil & Gas Operator | May 2025 |
| 667 | N & O Oil Co. | Imperial, TX 79743 | Oil & Gas Operator | May 2025 |
| 668 | Nadel And Gussman Permian,L.L.C. | Tulsa, OK 74103 | Oil & Gas Operator | May 2025 |
| 669 | Naumann Oil & Gas, Inc. | Austin, TX 78716 | Oil & Gas Operator | May 2025 |
| 670 | NBL Permian LLC | Houston, TX 77070 | Oil & Gas Operator | Aug 2018 |
| 671 | Nec Operating, LLC | Southlake, TX 76092 | Oil & Gas Operator | May 2025 |
| 672 | Neg Operating LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Nov 2024 |
| 673 | Nemo Fund I, LLC | Sugar Land, TX 77479 | Oil & Gas Operator | May 2017 |
| 674 | New Atlantis II, LLC | Big Spring, TX 79721 | Oil & Gas Operator | May 2025 |
| 675 | New Atlantis Oil & Expl., LLC | Big Spring, TX 79721 | Oil & Gas Operator | Feb 2012 |
| 676 | New Height Energy, LLC | Houston, TX 77063 | Oil & Gas Operator | May 2025 |
| 677 | Newfield Expl. Mid-Con. Inc | Tulsa, OK 74172 | Oil & Gas Operator | Jan 2015 |
| 678 | Newman Cubed, Inc. | Fort Worth, TX 76147 | Oil & Gas Operator | May 2025 |
| 679 | Newpark Environmental SVCS LLC | Lafayette, LA 70506 | Oil Operator | Jul 2014 |
| 680 | Newton Corp.,The | Dallas, TX 75251 | Oil & Gas Operator | May 2025 |
| 681 | Nicklos Oil & Gas Co. | Houston, TX 77252 | Oil & Gas Operator | Nov 1986 |
| 682 | Nizen, Stanley | FT Stockton, TX 79735 | Oil & Gas Operator | May 2002 |
| 683 | NMR Energy LLC | Houston, TX 77063 | Oil & Gas Operator | May 2025 |
| 684 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | May 2025 |
| 685 | Noble Operating, LLC | Flower Mound, TX 75028 | Oil & Gas Operator | Sep 2013 |
| 686 | Nokota Energy Corporation | Bakersfield, CA 93313 | Oil Operator | May 2025 |
| 687 | Noramco Production, LLC | Midland, TX 79710 | Oil & Gas Operator | Jan 2023 |
| 688 | Nordstrand Engineering Inc | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 689 | North American Royalties, Inc. | Chattanooga, TN 37408 | Oil & Gas Operator | Oct 2001 |
| 690 | North Central Casing Pullers,Inc | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 691 | North Operating Company | Canton, TX 75103 | Oil & Gas Operator | May 2025 |
| 692 | Northamerican Service Group | Katy, TX 77449 | Oil & Gas Operator | May 2025 |
| 693 | Northstar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 694 | Norwood, A. N., Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 1997 |
| 695 | O & O Operators, LLC. | Fate, TX 75132 | Oil & Gas Operator | May 2025 |
| 696 | O'Neill Properties, LTD. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 697 | O'Ryan Oil And Gas | Odessa, TX 79768 | Oil & Gas Operator | May 2025 |
| 698 | O. H. B. Inc. | San Angelo, TX 76902 | Oil & Gas Operator | Sep 2019 |
| 699 | Occidental Energy Company, Inc. | Houston, TX 77282 | Oil & Gas Operator | Jul 2021 |
| 700 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |