| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | Maple Gulf Coast Props. Corp. | Oil & Gas Operator | Jun 1989 | |
| 2 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Sep 2024 |
| 3 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | Sep 2024 |
| 4 | Maximus Operating, LTD. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 2024 |
| 5 | McGoldrick Oil Company | Shreveport, LA 71129 | Oil & Gas Operator | Jul 2020 |
| 6 | Mec-Goodrich Oil Co. | Oil & Gas Operator | Feb 1985 | |
| 7 | Mineral Ventures, Inc. | Oil & Gas Operator | Jun 2024 | |
| 8 | Mitchell Energy & Goodrich Oil | Oil & Gas Operator | Feb 1985 | |
| 9 | Mitchell Energy Company L.P. | Spring, TX 77387 | Oil & Gas Operator | Mar 2008 |
| 10 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 11 | Monsanto Oil Company | Oil & Gas Operator | Apr 1986 | |
| 12 | Mooringsport Energy Prod Corp | Oil & Gas Operator | Oct 1994 | |
| 13 | MRD Operating LLC | Oil & Gas Operator | Dec 2016 | |
| 14 | Munoco Co. | El Dorado, AR 71730 | Oil & Gas Operator | Jul 2021 |