| 3001 | Mid-Continent Energy Operating | | Gas Operator | Aug 2007 |
| 3002 | Mid-Continent Energy, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2020 |
| 3003 | Mid-National Resources Inc. | | Oil Operator | Feb 1999 |
| 3004 | Mid-South Trading, Inc. | | Oil & Gas Operator | Jan 2025 |
| 3005 | Middle Bay Oil Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 3006 | Middle Bay Production Co. Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2014 |
| 3007 | Mideast Gas Systems, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2005 |
| 3008 | Midla, LTD. | | Oil & Gas Operator | Jun 1990 |
| 3009 | Midland Workover, Inc. | | Oil & Gas Operator | Dec 2024 |
| 3010 | Midnight Drilling LLC | | Oil & Gas Operator | Jan 2016 |
| 3011 | Midroc Operating Company | | Oil & Gas Operator | Apr 2013 |
| 3012 | Midstates Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2000 |
| 3013 | Midstates Petroleum Company LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2018 |
| 3014 | Midstates Petroleum Corp. | | Oil & Gas Operator | Dec 2008 |
| 3015 | Midway Production Co. | | Gas Operator | May 1990 |
| 3016 | Midway Testing Company Inc | | Gas Operator | Mar 1984 |
| 3017 | Midwest Energy Companies, Inc. | | Oil & Gas Operator | Feb 1998 |
| 3018 | Midwest Enterprises, Inc. | Cashion, OK 73016-9626 | Oil & Gas Operator | Apr 2025 |
| 3019 | Mike Bonner | | Oil Operator | Aug 1999 |
| 3020 | Mil-Cro Inc. | | Oil Operator | Jan 1994 |
| 3021 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 3022 | Miles Oil & Gas Co. | | Oil & Gas Operator | Feb 1988 |
| 3023 | Millennium Offshore Group, Inc. | Houston, TX 77007 | Oil & Gas Operator | Sep 2005 |
| 3024 | Miller Exploration Company | Tulsa, OK 74136-1020 | Oil & Gas Operator | Mar 2015 |
| 3025 | Miller Oil Field Services, Inc | | Oil Operator | Feb 1990 |
| 3026 | Miller S.W.D., Inc. | | Oil Operator | Oct 2002 |
| 3027 | Milton Crow,Inc.&RP Evans Etal | | Oil & Gas Operator | Aug 1988 |
| 3028 | Milton Galoob | | Oil Operator | Dec 1988 |
| 3029 | Minatome Corpora | | Oil & Gas Operator | Sep 1987 |
| 3030 | Minden Oil & Gas, Inc. | | Oil & Gas Operator | May 1985 |
| 3031 | Mineral Development, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1996 |
| 3032 | Mineral Ventures, Inc. | | Oil & Gas Operator | Dec 2024 |
| 3033 | Minerex Engineering Corp. | | Oil & Gas Operator | Mar 2004 |
| 3034 | Miocene Oil & Gas, LTD. | Englewood, CO 80110 | Oil & Gas Operator | Sep 2025 |
| 3035 | Miss Chub LLC | | Gas Operator | Dec 2024 |
| 3036 | Miss Lou Oil Producers, Inc. | | Oil & Gas Operator | Dec 1998 |
| 3037 | Miss-Lou Operating LLC | | Oil & Gas Operator | Jul 2025 |
| 3038 | Miss-Lou Petroleum LLC | | Oil & Gas Operator | Jun 2011 |
| 3039 | Mission Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Sep 2025 |
| 3040 | Mission Exploration, Inc. | Fate, TX 75132 | Oil & Gas Operator | Dec 1987 |
| 3041 | Mission Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 3042 | Mission River Systems, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Sep 2025 |
| 3043 | Mississippi River Transm. Corp | | Oil & Gas Operator | Sep 2002 |
| 3044 | Mississippi Ventures | | Gas Operator | Feb 1992 |
| 3045 | Mitchell Energy & Goodrich Oil | | Oil & Gas Operator | Feb 1985 |
| 3046 | Mitchell Energy Company L.P. | Spring, TX 77387 | Oil & Gas Operator | Mar 2008 |
| 3047 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 3048 | MJ Energy, LLC | Denver, CO 80206 | Oil Operator | Jan 2025 |
| 3049 | MJ Energy, LLC Of Arkansas | | Oil Operator | Jan 2025 |
| 3050 | MJB Production Company, Inc. | Brownfield, TX 79316 | Oil & Gas Operator | Sep 2025 |
| 3051 | ML Resources, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 3052 | MLGW | | Gas Operator | Sep 1984 |
| 3053 | Mobil E&P N.A.-Pel-Tex | | Oil & Gas Operator | Dec 1993 |
| 3054 | Mobil E&P N.A.-WM Scully Et Al | | Oil & Gas Operator | Dec 1993 |
| 3055 | Mobil E&P North America Inc. | | Oil & Gas Operator | Jan 1994 |
| 3056 | Mobil Oil E & P Southeast Inc | | Oil & Gas Operator | Sep 2013 |
| 3057 | Mobil Oil E&P Se Inc - Pel-Tex | | Oil & Gas Operator | Dec 2005 |
| 3058 | Mobley & Davis | | Oil & Gas Operator | Oct 1986 |
| 3059 | Mobley & McCain | | Oil & Gas Operator | Nov 1979 |
| 3060 | Mobley & McCain, Et Al | | Oil & Gas Operator | Jul 1986 |
| 3061 | Mobley Oil Company, Inc. | | Oil & Gas Operator | Feb 1990 |
| 3062 | Mobley Valve Service, Inc. | | Oil & Gas Operator | Nov 2006 |
| 3063 | Moco Operating Company | | Oil & Gas Operator | Mar 2002 |
| 3064 | Mole Operating Co., Inc. | | Oil & Gas Operator | Oct 1983 |
| 3065 | Monarch Petroleum Corporation | FT Worth, TX 76102 | Oil & Gas Operator | Dec 2019 |
| 3066 | Monex | | Oil Operator | Apr 1988 |
| 3067 | Monexco, Inc. | | Oil Operator | Dec 2003 |
| 3068 | Mongrue Oil Company, Inc. | | Oil & Gas Operator | Oct 1999 |
| 3069 | Mongrue, Roland, Inc | | Oil & Gas Operator | Mar 1979 |
| 3070 | Monroe Gas Associates-1 | | Gas Operator | Mar 2000 |
| 3071 | Monroe Gas Joint Venture | | Gas Operator | Sep 2011 |
| 3072 | Monroe Well Ser-Amsterdam | | Oil Operator | Dec 1988 |
| 3073 | Monroe Well Ser-La Petr Assoc | | Oil Operator | Dec 1988 |
| 3074 | Monroe Well Ser-La Petro II | | Oil Operator | Dec 1988 |
| 3075 | Monroe Well Ser-New American85 | | Oil Operator | Dec 1988 |
| 3076 | Monroe Well Ser-Ocean Petr '84 | | Oil & Gas Operator | Dec 1988 |
| 3077 | Monroe Well Ser-Ocean Yacht II | | Oil Operator | May 1989 |
| 3078 | Monroe Well Ser-Oceanyacht1985 | | Oil Operator | Dec 1988 |
| 3079 | Monroe Well Ser-Riverside 1985 | | Oil Operator | Dec 1988 |
| 3080 | Monroe Well Serv-New American | | Oil Operator | Dec 1988 |
| 3081 | Monroe Well Serv-Northern La | | Oil Operator | Dec 1988 |
| 3082 | Monroe Well Serv-Omega 1985 | | Oil Operator | Dec 1988 |
| 3083 | Monroe Well Service | | Oil & Gas Operator | Apr 1998 |
| 3084 | Monroe Well Service-Ajk | | Oil Operator | Dec 1988 |
| 3085 | Monroe Well Service-Apk | | Oil Operator | Dec 1988 |
| 3086 | Monroe Well Service-Beaver1985 | | Oil Operator | Nov 1991 |
| 3087 | Monroe Well Service-Broadway | | Oil Operator | Dec 1988 |
| 3088 | Monroe Well Service-BWK | | Oil Operator | Dec 1988 |
| 3089 | Monroe Well Service-Columbus | | Oil Operator | Dec 1988 |
| 3090 | Monroe Well Service-Das | | Oil Operator | Mar 1989 |
| 3091 | Monroe Well Service-Derrick | | Oil Operator | Dec 1988 |
| 3092 | Monroe Well Service-East End | | Oil Operator | Dec 1988 |
| 3093 | Monroe Well Service-Empire | | Oil Operator | Dec 1988 |
| 3094 | Monroe Well Service-Energy | | Oil Operator | Dec 1988 |
| 3095 | Monroe Well Service-Energy 84 | | Oil Operator | Aug 1989 |
| 3096 | Monroe Well Service-Ged | | Oil Operator | Dec 1988 |
| 3097 | Monroe Well Service-Gotham | | Oil Operator | Apr 1992 |
| 3098 | Monroe Well Service-Gramercy | | Oil Operator | May 1992 |
| 3099 | Monroe Well Service-HGC | | Oil Operator | Dec 1988 |
| 3100 | Monroe Well Service-Lebo | | Oil Operator | Jun 1989 |