| 1 | Mac Laskey Kelly Oilfield | El Dorado, KS 67042 | Oil & Gas Operator | Feb 2024 |
| 2 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Mar 2024 |
| 3 | Marjo Operating Mid-Continent LLC | | Oil & Gas Operator | Feb 2024 |
| 4 | Meade Energy Corporation | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | Feb 2024 |
| 5 | Meade James C | Oklahoma City, OK 73118-1544 | Gas Operator | Apr 2015 |
| 6 | Medallion Energy Inc | Norman, OK 73072-7436 | Oil & Gas Operator | Aug 2004 |
| 7 | Medallion Petroleum, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2015 |
| 8 | Mendell Petroleum Corporation | Castle Rock, CO 80104-9045 | Oil & Gas Operator | Sep 2004 |
| 9 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2024 |
| 10 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | May 2024 |
| 11 | Mid-Con Central Expl Co | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2014 |
| 12 | Midwest Energy Corporation | Tulsa, OK 74105-6083 | Oil & Gas Operator | Aug 2016 |
| 13 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 14 | Mobil Exp & Prod Us Inc | Houston, TX 77060-1991 | Oil & Gas Operator | May 2001 |
| 15 | Moore Richard L | Morris, OK 74445 | Oil Operator | Aug 2013 |
| 16 | Mountain Front Pipeline Co, Inc | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 17 | Mud Operations Inc | Ames, OK 73718-9501 | Oil & Gas Operator | Feb 2024 |
| 18 | Mueller Thomas C | Fort Smith, AR 72913 | Gas Operator | Aug 2008 |
| 19 | Mustang Fuel Corp. Of Oklahoma | Oklahoma City, OK 73106 | Oil & Gas Operator | Nov 2016 |
| 20 | Mustang Fuel Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2024 |