| 3001 | Merlin J Verret | | Gas Operator | Jun 1986 |
| 3002 | Merrico Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2008 |
| 3003 | Merritt Operating, Inc. | Mineola, TX 75773 | Oil & Gas Operator | Dec 2025 |
| 3004 | Mertz Energy LLC | Houston, TX 77098 | Oil & Gas Operator | Jan 2025 |
| 3005 | Mesa Gulf Coast LLC | | Oil & Gas Operator | Dec 2020 |
| 3006 | Mesa Operating LTD Partnership | Amarillo, TX 79189 | Oil & Gas Operator | May 1994 |
| 3007 | Mesa Petroleum Co. | | Oil & Gas Operator | Aug 1985 |
| 3008 | Mescalero Energy, Inc. | San Antonio, TX 78231 | Oil & Gas Operator | Aug 2003 |
| 3009 | Metairie Energy Company, Inc. | | Oil & Gas Operator | Nov 2019 |
| 3010 | Metro Energy Group, Inc. | Bossier City, LA 71112 | Oil & Gas Operator | May 2013 |
| 3011 | Mettz,Carmody & Foster Oil Co | | Oil Operator | May 1990 |
| 3012 | Meyers-Lasher, Inc. | | Oil & Gas Operator | Mar 1999 |
| 3013 | MFP Petroleum LTD. Partnership | Oklahoma City, OK 73142 | Oil & Gas Operator | Nov 2017 |
| 3014 | MGF Oil Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1998 |
| 3015 | Mich-La Oil & Gas Exploration | | Oil & Gas Operator | Jan 1992 |
| 3016 | Michael D Brown | | Oil Operator | Jul 1993 |
| 3017 | Michael W Mills | | Oil Operator | Jul 2007 |
| 3018 | Michel T. Halbouty | | Oil & Gas Operator | Dec 1996 |
| 3019 | Michel T. Halbouty Energy Co. | | Oil & Gas Operator | Nov 1986 |
| 3020 | Michigan-Wisconsin Pipe Line Co | | Oil & Gas Operator | Dec 1983 |
| 3021 | Micron Minerals Company | | Oil & Gas Operator | Sep 1988 |
| 3022 | Mid Field Oil Co. | | Oil & Gas Operator | Mar 1989 |
| 3023 | Mid Louisiana Gas Company | | Oil & Gas Operator | Oct 2002 |
| 3024 | Mid South Oil & Gas Expl Inc | | Oil & Gas Operator | Jan 1992 |
| 3025 | Mid-America Resources Corporation | | Oil Operator | Jan 2019 |
| 3026 | Mid-America Resources, Inc. | | Oil & Gas Operator | Feb 2008 |
| 3027 | Mid-America/Hughes & Hughes | | Oil Operator | Jul 1984 |
| 3028 | Mid-Con Energy Operating, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | May 2020 |
| 3029 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 3030 | Mid-Continent Energy Operating | | Gas Operator | Aug 2007 |
| 3031 | Mid-Continent Energy, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2020 |
| 3032 | Mid-National Resources Inc. | | Oil Operator | Feb 1999 |
| 3033 | Mid-South Trading, Inc. | | Oil & Gas Operator | Jan 2025 |
| 3034 | Middle Bay Oil Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 3035 | Middle Bay Production Co. Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2014 |
| 3036 | Mideast Gas Systems, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2005 |
| 3037 | Midla, LTD. | | Oil & Gas Operator | Jun 1990 |
| 3038 | Midland Workover, Inc. | | Oil & Gas Operator | Dec 2024 |
| 3039 | Midnight Drilling LLC | | Oil & Gas Operator | Jan 2016 |
| 3040 | Midroc Operating Company | | Oil & Gas Operator | Apr 2013 |
| 3041 | Midstates Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2000 |
| 3042 | Midstates Petroleum Company LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2018 |
| 3043 | Midstates Petroleum Corp. | | Oil & Gas Operator | Dec 2008 |
| 3044 | Midway Production Co. | | Gas Operator | May 1990 |
| 3045 | Midway Testing Company Inc | | Gas Operator | Mar 1984 |
| 3046 | Midwest Energy Companies, Inc. | | Oil & Gas Operator | Feb 1998 |
| 3047 | Midwest Enterprises Inc | Cashion, OK 73016-9626 | Oil & Gas Operator | Apr 2025 |
| 3048 | Mike Bonner | | Oil Operator | Aug 1999 |
| 3049 | Mil-Cro Inc. | | Oil Operator | Jan 1994 |
| 3050 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 3051 | Miles Oil & Gas Co. | | Oil & Gas Operator | Feb 1988 |
| 3052 | Millennium Offshore Group, Inc. | Houston, TX 77007 | Oil & Gas Operator | Sep 2005 |
| 3053 | Miller Exploration Company | Tulsa, OK 74136-1020 | Oil & Gas Operator | Mar 2015 |
| 3054 | Miller Oil Field Services, Inc | | Oil Operator | Feb 1990 |
| 3055 | Miller S.W.D., Inc. | | Oil Operator | Oct 2002 |
| 3056 | Milton Crow,Inc.&RP Evans Etal | | Oil & Gas Operator | Aug 1988 |
| 3057 | Milton Galoob | | Oil Operator | Dec 1988 |
| 3058 | Minatome Corpora | | Oil & Gas Operator | Sep 1987 |
| 3059 | Minden Oil & Gas, Inc. | | Oil & Gas Operator | May 1985 |
| 3060 | Mineral Development, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1996 |
| 3061 | Mineral Ventures, Inc. | | Oil & Gas Operator | Dec 2024 |
| 3062 | Minerex Engineering Corp. | | Oil & Gas Operator | Mar 2004 |
| 3063 | Miocene Oil & Gas, LTD. | Englewood, CO 80110 | Oil & Gas Operator | Dec 2025 |
| 3064 | Miss Chub LLC | | Gas Operator | Dec 2024 |
| 3065 | Miss-Lou Oil Producers Inc | | Oil & Gas Operator | Dec 1998 |
| 3066 | Miss-Lou Operating LLC | | Oil & Gas Operator | Sep 2025 |
| 3067 | Miss-Lou Petroleum LLC | | Oil & Gas Operator | Jun 2011 |
| 3068 | Mission Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 3069 | Mission Exploration, Inc. | Fate, TX 75132 | Oil & Gas Operator | Dec 1987 |
| 3070 | Mission Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 3071 | Mission River Systems, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Dec 2025 |
| 3072 | Mississippi River Transm. Corp | | Oil & Gas Operator | Sep 2002 |
| 3073 | Mississippi Ventures | | Gas Operator | Feb 1992 |
| 3074 | Mitchell Energy & Goodrich Oil | | Oil & Gas Operator | Feb 1985 |
| 3075 | Mitchell Energy Company L.P. | Spring, TX 77387 | Oil & Gas Operator | Mar 2008 |
| 3076 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 3077 | MJ Energy LLC | Denver, CO 80206 | Oil Operator | Jan 2025 |
| 3078 | MJ Energy, LLC Of Arkansas | | Oil Operator | Jan 2025 |
| 3079 | MJB Production Company, Inc. | Brownfield, TX 79316 | Oil & Gas Operator | Dec 2025 |
| 3080 | ML Resources, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 3081 | MLGW | | Gas Operator | Sep 1984 |
| 3082 | Mobil E&P N.A.-Pel-Tex | | Oil & Gas Operator | Dec 1993 |
| 3083 | Mobil E&P N.A.-WM Scully Et Al | | Oil & Gas Operator | Dec 1993 |
| 3084 | Mobil E&P North America Inc. | | Oil & Gas Operator | Jan 1994 |
| 3085 | Mobil Oil E & P Southeast Inc | | Oil & Gas Operator | Sep 2013 |
| 3086 | Mobil Oil E&P Se Inc - Pel-Tex | | Oil & Gas Operator | Dec 2005 |
| 3087 | Mobley & Davis | | Oil & Gas Operator | Oct 1986 |
| 3088 | Mobley & McCain | | Oil & Gas Operator | Nov 1979 |
| 3089 | Mobley & McCain, Et Al | | Oil & Gas Operator | Jul 1986 |
| 3090 | Mobley Oil Company, Inc. | | Oil & Gas Operator | Feb 1990 |
| 3091 | Mobley Valve Service, Inc. | | Oil & Gas Operator | Nov 2006 |
| 3092 | Moco Operating Company | | Oil & Gas Operator | Mar 2002 |
| 3093 | Mole Operating Co., Inc. | | Oil & Gas Operator | Oct 1983 |
| 3094 | Monarch Petroleum Corporation | FT Worth, TX 76102 | Oil & Gas Operator | Dec 2019 |
| 3095 | Monex | | Oil Operator | Apr 1988 |
| 3096 | Monexco, Inc. | | Oil Operator | Dec 2003 |
| 3097 | Mongrue Oil Company, Inc. | | Oil & Gas Operator | Oct 1999 |
| 3098 | Mongrue, Roland, Inc | | Oil & Gas Operator | Mar 1979 |
| 3099 | Monroe Gas Associates-1 | | Gas Operator | Mar 2000 |
| 3100 | Monroe Gas Associates-2 | | Gas Operator | Mar 2000 |