| 1 | Makar Production Company | Amarillo, TX 79118 | Oil & Gas Operator | May 2024 |
| 2 | Marsh Operating Company | Dallas, TX 75221 | Oil & Gas Operator | Jan 2024 |
| 3 | Maxus Exploration Company | Dallas, TX 75201 | Oil & Gas Operator | Jan 1995 |
| 4 | McDaniel Company, Inc., The | Dallas, TX 75230 | Oil & Gas Operator | May 2024 |
| 5 | McKinney Operating Company | Canadian, TX 79014 | Gas Operator | May 2002 |
| 6 | McNic Oil & Gas Midcontinent,Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 1999 |
| 7 | Medallion Petroleum, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2015 |
| 8 | Medallion Production Company | Tulsa, OK 74103 | Oil & Gas Operator | May 1997 |
| 9 | Merex Resources, Inc. | Amarillo, TX 79159 | Oil & Gas Operator | Sep 2019 |
| 10 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 11 | Meridian Oil Production Inc. | Houston, TX 77210 | Oil & Gas Operator | Oct 2022 |
| 12 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2024 |
| 13 | Mesa Operating LTD Partnership | Amarillo, TX 79189 | Oil & Gas Operator | May 1994 |
| 14 | Mesa VIsta Operating, LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2024 |
| 15 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | May 2024 |
| 16 | Mge Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jan 2024 |
| 17 | Midgard Energy Company | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 18 | Mitchell Ehrlich Oil & Gas, LLC | Austin, TX 78746 | Oil & Gas Operator | May 2024 |
| 19 | MMGL TXPH, LLC | Dallas, TX 75240 | Oil & Gas Operator | May 2024 |
| 20 | Momentum Operating Co., Inc. | Albany, TX 76430 | Oil & Gas Operator | May 2024 |
| 21 | Mon Corp. | Pampa, TX 79066 | Oil & Gas Operator | May 2024 |
| 22 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 23 | Moore, Stephen Operating | Graham, TX 76450 | Oil & Gas Operator | Jun 2002 |
| 24 | Munson Operating, Inc. | Dallas, TX 75251 | Oil & Gas Operator | May 2024 |
| 25 | Mustang Fuel Corp. Of Oklahoma | Oklahoma City, OK 73106 | Oil & Gas Operator | Nov 2016 |
| 26 | Mustang Fuel Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2024 |
| 27 | Myriad Resources Corporation | Pampa, TX 79066 | Oil & Gas Operator | May 2024 |