| 1 | M. E. Operating & Services, Inc. | Fort Worth, TX 76104 | Oil & Gas Operator | Apr 2024 |
| 2 | M.B.J. Operating | Argyle, TX 76226 | Oil & Gas Operator | Jun 2022 |
| 3 | Machin & Associates, Inc. | Longview, TX 75606 | Oil & Gas Operator | Apr 2024 |
| 4 | Magna Oil & Gas Corporation | Irving, TX 75017 | Oil & Gas Operator | Feb 2016 |
| 5 | Manziel Management Corporation | Tyler, TX 75711 | Oil Operator | Feb 2014 |
| 6 | Map Production Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 7 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Feb 2024 |
| 8 | Martin Foree Operating II, LLC | Royse City, TX 75189 | Oil & Gas Operator | Apr 2024 |
| 9 | Martin Foree Operating, LLC | Royse City, TX 75189 | Oil & Gas Operator | Apr 2024 |
| 10 | Matador Operating Company | Dallas, TX 75240 | Oil & Gas Operator | Jul 2003 |
| 11 | Maximus Operating, LTD. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 12 | McQueen Ed & Company Inc | Lindsey, OK 73052 | Oil & Gas Operator | Apr 2014 |
| 13 | Meadows Oil Company | Plano, TX 75075 | Oil & Gas Operator | Aug 2004 |
| 14 | Mercury Operating, LLC | Dallas, TX 75208 | Oil & Gas Operator | Apr 2024 |
| 15 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Apr 2024 |
| 16 | Mitchell Energy Company L.P. | Spring, TX 77387 | Oil & Gas Operator | Mar 2008 |
| 17 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 18 | ML Resources, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 19 | MLC Operating, LP | Houston, TX 77063 | Oil & Gas Operator | Apr 2024 |
| 20 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 21 | Mortimer Exploration Company | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2003 |
| 22 | Mosbacher Energy Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2024 |
| 23 | Mud Creek Operating, LLC | Tyler, TX 75702 | Oil & Gas Operator | Apr 2024 |
| 24 | Mueller Exploration, Inc. | Portland, TX 78374 | Oil & Gas Operator | Apr 2024 |
| 25 | Mustang Drilling, LTD. | Henderson, TX 75653 | Oil & Gas Operator | May 2008 |