| 1 | M.T.M. Petroleum | | Oil & Gas Operator | Oct 1995 |
| 2 | Mack Energy Co. | Duncan, OK 73534 | Oil & Gas Operator | Feb 2026 |
| 3 | Mack Energy Comp | | Oil & Gas Operator | Nov 1994 |
| 4 | Manuel Corporation | Wichita, KS 67206 | Oil & Gas Operator | Feb 2026 |
| 5 | Marathon Oil Com | | Oil & Gas Operator | Dec 1996 |
| 6 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Feb 2026 |
| 7 | Martin Oil Produ | | Oil & Gas Operator | Dec 1994 |
| 8 | Martin Oil Producers, Inc. | Garland, TX 75046 | Oil & Gas Operator | Aug 2013 |
| 9 | McCoy Petroleum | | Oil & Gas Operator | Aug 1996 |
| 10 | McCoy Petroleum Corporation | Wichita, KS 67207 | Oil & Gas Operator | Feb 2026 |
| 11 | McGinness Energy Company Inc | Wichita, KS 67206 | Oil & Gas Operator | Jan 2026 |
| 12 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Apr 2026 |
| 13 | Merit Energy Company, LLC | Dallas, TX 75009 | Oil & Gas Operator | Dec 2025 |
| 14 | Messenger Petroleum, Inc. | Kingman, KS 67068 | Oil & Gas Operator | Dec 2025 |
| 15 | Mid-Continent Energy Corp. | Wichita, KS 67208 | Oil & Gas Operator | Dec 2025 |
| 16 | Midco Exploration, Inc. | Westmont, IL 60559 | Oil & Gas Operator | Dec 2025 |
| 17 | Middle Bay Production Co. Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2014 |
| 18 | MKJ Oil Co LLC | Harper, KS 67058 | Oil & Gas Operator | Dec 2025 |
| 19 | Mobil Oil Corpor | | Oil & Gas Operator | Dec 1996 |
| 20 | Molitor Oil, Inc. | Wichita, KS 67205 | Oil & Gas Operator | Dec 2025 |
| 21 | Monsanto Oil Com | | Oil Operator | Nov 1996 |
| 22 | MTM Petroleum, Inc. | Kingman, KS 67068 | Oil & Gas Operator | Dec 2025 |
| 23 | Mull Drilling Company | Wichita, KS 67206 | Oil & Gas Operator | Jan 2026 |
| 24 | Murfin Drilling Company, Inc. | Wichita, KS 67202 | Oil & Gas Operator | Feb 2026 |
| 25 | Musgrove Energy Inc | Ponca City, OK 74602 | Oil & Gas Operator | Dec 2025 |