| 1 | M-C Production & Drilling Co,Inc | Longview, TX 75608 | Oil & Gas Operator | Mar 2025 |
| 2 | Magna Oil & Gas Corporation | Irving, TX 75017 | Oil & Gas Operator | Feb 2016 |
| 3 | Manziel Management Corporation | Tyler, TX 75711 | Oil Operator | Feb 2014 |
| 4 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 5 | Maximus Operating, LTD. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 6 | Mayfield Energy, LLC | Austin, TX 78732 | Oil & Gas Operator | Mar 2025 |
| 7 | McBee Company, The | Dallas, TX 75219 | Oil & Gas Operator | Dec 1997 |
| 8 | McBride, Jerrel L Enterprise Inc | Kilgore, TX 75663 | Oil & Gas Operator | Jun 1999 |
| 9 | McCulliss Resources Co Inc | Littleton, CO 80161-3248 | Oil & Gas Operator | Jun 2009 |
| 10 | McMurrey, R. J., Production Comp | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 11 | Medallion Production Company | Tulsa, OK 74103 | Oil & Gas Operator | May 1997 |
| 12 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 13 | Micro Operating, Inc. | Bryan, TX 77807 | Oil & Gas Operator | Mar 2025 |
| 14 | Millennium Exploration Co. LLC | San Antonio, TX 78232 | Oil & Gas Operator | Mar 2025 |
| 15 | Miller Energy Inc | Houston, TX 77024 | Oil & Gas Operator | Oct 2016 |
| 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 | MMGL East Texas II, LLC | Dallas, TX 75240 | Oil & Gas Operator | Mar 2025 |
| 19 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 20 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 21 | Momentum Operating Co., Inc. | Albany, TX 76430 | Oil & Gas Operator | Mar 2025 |
| 22 | Montare Operating, LTD. | Flower Mound, TX 75022 | Oil & Gas Operator | Mar 2025 |
| 23 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 24 | Moon Operating, Inc. | Longview, TX 75601 | Oil & Gas Operator | Mar 2003 |
| 25 | Mosbacher Energy Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 26 | Murphy, K. P. Oil Operator | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |