| 1 | M & K Operating LLC | Albany, TX 76430 | Oil & Gas Operator | Oct 2025 |
| 2 | M-B Operating Co., Inc. | Rowlett, TX 75030 | Oil & Gas Operator | Oct 2025 |
| 3 | M.R.M. Operating, Inc. | Midland, TX 79707 | Oil & Gas Operator | Aug 2003 |
| 4 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | Aug 2025 |
| 5 | Mathis & Sons, Inc. | Rule, TX 79547 | Oil & Gas Operator | Oct 2025 |
| 6 | Maynard Oil Co. | Denver, CO 80202 | Oil & Gas Operator | Sep 2004 |
| 7 | Mayo, Eddie | Fredericksbrg, TX 78624 | Oil & Gas Operator | Oct 2025 |
| 8 | Mayo, Paul R. | Quinlan, TX 75474 | Oil & Gas Operator | May 1999 |
| 9 | McBee Company, The | Dallas, TX 75219 | Oil & Gas Operator | Dec 1997 |
| 10 | McClymond, LTD. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2009 |
| 11 | McFarland & Scobey, Inc. | El Paso, TX 79947 | Oil & Gas Operator | Oct 2025 |
| 12 | McKeever, Tyra, Swenson Venture | Stamford, TX 79553 | Oil & Gas Operator | Apr 1996 |
| 13 | Mercury Exploration Co | Fort Worth, TX 76104 | Oil & Gas Operator | Dec 2006 |
| 14 | Mercury Operating, LLC | Dallas, TX 75208 | Oil & Gas Operator | Oct 2025 |
| 15 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Oct 2025 |
| 16 | Mexco Energy Corporation | Midland, TX 79702 | Oil & Gas Operator | Feb 2020 |
| 17 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2025 |
| 18 | Mid-Continental Exploration,Inc. | Sanger, TX 76266 | Oil & Gas Operator | Oct 2025 |
| 19 | Midland Oil And Gas, Inc. | Midland, TX 79705 | Oil & Gas Operator | Oct 2025 |
| 20 | Miles Production Co. | Argyle, TX 76226 | Oil & Gas Operator | Mar 2008 |
| 21 | Mineral Development, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1996 |
| 22 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 23 | MJM Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 24 | MMG Oil Company | Buffalo Gap, TX 79508 | Oil & Gas Operator | Aug 2006 |
| 25 | Mna Enterprises LTD. Co. | Hobbs, NM 88242 | Oil & Gas Operator | Jul 2025 |
| 26 | Moore Investment Co. | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 27 | Morrell, W. R. | Albany, TX 76430 | Oil & Gas Operator | Oct 2025 |
| 28 | Morris, W. Dale Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | Oct 2025 |
| 29 | Mullins, Manuel | Olney, TX 76374 | Oil & Gas Operator | Oct 2025 |
| 30 | Musselman, Owen & King Oper.,Inc | Houston, TX 77002 | Oil & Gas Operator | Feb 1998 |
| 31 | MWJ Producing Company | Midland, TX 79701 | Oil & Gas Operator | Jul 1998 |
| 32 | Myco Industries, Inc. | Artesia, NM 88211 | Oil & Gas Operator | Feb 2015 |