| 1 | Machin & Associates, Inc. | Longview, TX 75606 | Oil & Gas Operator | Oct 2025 |
| 2 | Magnum Producing, LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Oct 2025 |
| 3 | Marmaton Oil Company | Houston, TX 77002 | Oil & Gas Operator | Jul 1998 |
| 4 | Martineau Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Jan 2025 |
| 5 | McDaniel Company, Inc., The | Dallas, TX 75230 | Oil & Gas Operator | Oct 2025 |
| 6 | McDonnold Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 7 | McGehee, George T. Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 1997 |
| 8 | Memorial Exploration Company | Saint Louis, MO 63105 | Oil & Gas Operator | Aug 1996 |
| 9 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 10 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Oct 2025 |
| 11 | Middle Bay Oil Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 12 | Milestone Operating, Inc. | Montgomery, TX 77316 | Oil & Gas Operator | Oct 2025 |
| 13 | Miller Energy Inc | Houston, TX 77024 | Oil & Gas Operator | Oct 2016 |
| 14 | Miocene Oil & Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Jul 1998 |
| 15 | Miocene Oil & Gas, LTD. | Englewood, CO 80110 | Oil & Gas Operator | Oct 2025 |
| 16 | Morgan Enterprises, Inc. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 17 | Morris, W. Dale Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | Oct 2025 |
| 18 | Mosman Operating, LLC | Dallas, TX 75204 | Oil Operator | Oct 2025 |
| 19 | Murphy Exploration & Prod. Co. | Houston, TX 77094 | Oil & Gas Operator | Jun 2011 |
| 20 | Murphy Oil USA Inc | New Orleans, LA 70161 | Oil & Gas Operator | Jan 1993 |
| 21 | Mustang Drilling, Inc. | Henderson, TX 75653 | Oil & Gas Operator | Aug 2024 |
| 22 | Mustang Drilling, LTD. | Henderson, TX 75653 | Oil & Gas Operator | May 2008 |