| 1 | M M Energy, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Apr 2025 |
| 2 | M M Resources, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Sep 2018 |
| 3 | Mach Petroleum, Inc. | Tulsa, OK 74153 | Oil & Gas Operator | Nov 2014 |
| 4 | Mack Energy Co. | Duncan, OK 73534 | Oil & Gas Operator | May 2025 |
| 5 | Mackellar Inc | Oklahoma City, OK 73116-7101 | Oil & Gas Operator | May 2025 |
| 6 | Magnum Energy Inc | Norman, OK 73072-2403 | Oil & Gas Operator | May 2025 |
| 7 | Majors Jimmy R | Osceola, NE 68651-0726 | Oil & Gas Operator | Sep 2000 |
| 8 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 9 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | May 2025 |
| 10 | Mark Holloway Inc | Oklahoma City, OK 73107-6526 | Oil & Gas Operator | Apr 2025 |
| 11 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | May 2025 |
| 12 | Marshall Oil Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Apr 2017 |
| 13 | Maverick Brothers Resources LLC | Enid, OK 73701 | Oil & Gas Operator | Apr 2025 |
| 14 | May Petroleum, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Nov 1998 |
| 15 | McNic Oil & Gas Midcontinent | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | May 2024 |
| 16 | Meade Energy Corporation | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | May 2025 |
| 17 | Meador Oil Company Inc | Lubbock, TX 79415 | Oil & Gas Operator | Oct 2022 |
| 18 | Medallion Petroleum, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2015 |
| 19 | Medicine Bow Operating Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2014 |
| 20 | Mep Operating LLC | Houston, TX 77056-2733 | Oil & Gas Operator | Apr 2025 |
| 21 | Mer Resources Inc | Edmond, OK 73013-7662 | Oil & Gas Operator | Mar 2015 |
| 22 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Jul 2025 |
| 23 | Mermac Operating Company Inc | Norman, OK 73072 | Oil & Gas Operator | Mar 2015 |
| 24 | Mesa Operating LP | Irving, TX 75039-3746 | Oil & Gas Operator | Oct 2010 |
| 25 | Metropolitan Resources Corp | Tulsa, OK 74169-1734 | Oil & Gas Operator | Mar 2015 |
| 26 | Mid-Con Central Expl Co | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2014 |
| 27 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2025 |
| 28 | Midnight Hour LLC | Enid, OK 73702 | Oil & Gas Operator | Apr 2020 |
| 29 | Midwest Energy Corporation | Tulsa, OK 74105-6083 | Oil & Gas Operator | Aug 2016 |
| 30 | Midwest Pipe & Supply Company | Oklahoma City, OK 73154-0245 | Oil & Gas Operator | Dec 2008 |
| 31 | Milmac Operating Company | Lubbock, TX 79408-2976 | Oil & Gas Operator | Sep 2004 |
| 32 | Mito Resources LLC | Edmond, OK 73013 | Oil & Gas Operator | May 2025 |
| 33 | Mobil Exp & Prod Us Inc | Houston, TX 77060-1991 | Oil & Gas Operator | May 2001 |
| 34 | Monroe Natural Gas Inc | Norman, OK 73071 | Oil & Gas Operator | Apr 2025 |
| 35 | Monty L Hott Production Corporation | Oklahoma City, OK 73142 | Oil & Gas Operator | Apr 2025 |
| 36 | Moore Petroleum Invest Corp | Norman, OK 73072-4217 | Oil & Gas Operator | Apr 2025 |
| 37 | Mud Operations Inc | Ames, OK 73718-9501 | Oil & Gas Operator | Apr 2025 |
| 38 | Muras Energy Inc | Edmond, OK 73013 | Oil & Gas Operator | Apr 2025 |
| 39 | Mustang Fuel Corp. Of Oklahoma | Oklahoma City, OK 73106 | Oil & Gas Operator | Nov 2016 |
| 40 | Mustang Fuel Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | May 2025 |
| 41 | Mustang Gas Products LLC | Oklahoma City, OK 73114-7406 | Oil & Gas Operator | Sep 2022 |
| 42 | MW Petroleum Corporation | Houston, TX 77056 | Oil & Gas Operator | Mar 2015 |