| 18001 | Maranatha Energy Corporation | Athens, WV 24712 | Oil & Gas Operator | Dec 2021 |
| 18002 | Maranatha Exploration Inc | Killbuck, OH 44637 | Oil & Gas Operator | Dec 1992 |
| 18003 | Maranatha Exploration, LP | Wichita Falls, TX 76307 | Oil Operator | Feb 2012 |
| 18004 | Maranatha Oil Company | Gonzales, TX 78629 | Oil & Gas Operator | Jul 2025 |
| 18005 | Maranatha Petroleum Inc. | | Oil & Gas Operator | Apr 2025 |
| 18006 | Marata Oil & Gas Company | Dallas, TX 75225 | Oil & Gas Operator | Aug 2003 |
| 18007 | Marathon Corporation | | Oil Operator | Dec 1994 |
| 18008 | Marathon Oil Co.-Rocky Mountain Region | Cody, WY 82414 | Oil Operator | Dec 1999 |
| 18009 | Marathon Oil Com | | Oil & Gas Operator | Dec 1996 |
| 18010 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | May 2025 |
| 18011 | Marathon Oil Company Operator | | Oil & Gas Operator | Dec 1993 |
| 18012 | Marathon Oil Company/Fina | | Oil & Gas Operator | Jan 2005 |
| 18013 | Marathon Oil Ef LLC | Houston, TX 77252 | Oil & Gas Operator | Jul 2025 |
| 18014 | Marathon Oil Permian LLC | Midland, TX 79701 | Oil & Gas Operator | May 2025 |
| 18015 | Marben Corporation | | Oil Operator | Jul 1995 |
| 18016 | Marbet LLC | Edmond, OK 73013-6691 | Oil & Gas Operator | Apr 2025 |
| 18017 | Marbil Oil, Inc. | Olney, TX 76374 | Oil & Gas Operator | Jun 2013 |
| 18018 | Marbob Energy Corp | Artesia, NM 882110227 | Oil & Gas Operator | Oct 2010 |
| 18019 | Marchman, J. E. | Graham, TX 76450 | Oil & Gas Operator | Jul 2009 |
| 18020 | Marco Drilling Inc | Monroeville, PA 15146-0278 | Oil & Gas Operator | Dec 2024 |
| 18021 | Marco Land & Petroleum, Inc. | | Oil & Gas Operator | Jun 2000 |
| 18022 | Marco Oil Co, Inc | Sparta, KY 41086 | Oil Operator | Dec 2021 |
| 18023 | Marco Oil Compan | | Oil & Gas Operator | Aug 1992 |
| 18024 | Marco Oil Company LLC | Bartlesville, OK 74005 | Oil & Gas Operator | Apr 2025 |
| 18025 | Marco Polo Exploration, Inc. | Rosenberg, TX 77471 | Oil & Gas Operator | Dec 1993 |
| 18026 | Marcon Operating Company, Inc. | Bridgeport, TX 76426 | Oil & Gas Operator | Oct 2011 |
| 18027 | Marconi Exploration, Inc. | Houston, TX 77056 | Oil & Gas Operator | Aug 1997 |
| 18028 | Marcum Drilling Co. | Midland, TX 79701 | Oil & Gas Operator | Aug 2002 |
| 18029 | Marcus Exploration Inc | Piedmont, OK 73078-0308 | Oil & Gas Operator | Dec 2000 |
| 18030 | Mardale Drilling Company | Oklahoma City, OK 73157 | Oil Operator | Nov 1998 |
| 18031 | Marden Petroleum Exp Co | Marietta, OH 45750 | Oil & Gas Operator | Dec 1990 |
| 18032 | Marden Producing | | Gas Operator | Aug 1990 |
| 18033 | Marden Producing Company | Edmond, OK 73083 | Gas Operator | Mar 2025 |
| 18034 | Mare Energy | Danville, OH 43014 | Oil & Gas Operator | Dec 2021 |
| 18035 | Mare Energy LLC | Danville, OH 43014 | Oil & Gas Operator | Dec 2024 |
| 18036 | Marexco | | Oil & Gas Operator | Nov 1994 |
| 18037 | Marexco, Inc. | Castle Rock, CO 80104 | Oil & Gas Operator | Mar 2025 |
| 18038 | Margaret Merganser Inc | Tionesta, PA 16353-5853 | Oil & Gas Operator | Dec 2008 |
| 18039 | Maria L. Andrade | | Oil Operator | Dec 2006 |
| 18040 | Mariah Energy Corp. | Austin, TX 78716 | Oil & Gas Operator | Apr 1999 |
| 18041 | Mariah Exploration LLC | Pawhuska, OK 74056 | Oil & Gas Operator | Oct 2008 |
| 18042 | Mariah Operating Company, LLC | Denver, CO 80201 | Oil & Gas Operator | Dec 2009 |
| 18043 | Marianas Operating Co. | Abilene, TX 79601 | Oil & Gas Operator | Aug 2003 |
| 18044 | Marieff Petroleum, Inc. | Sagamore Hills, OH 44067 | Gas Operator | Dec 2024 |
| 18045 | Marienfeld Exploration | Houston, TX 77005 | Oil & Gas Operator | Mar 1994 |
| 18046 | Marienfeld Exploration, Inc. | Ojai, CA 93024 | Oil & Gas Operator | Jul 2025 |
| 18047 | Marietta Royalty Co Inc | Stillwater, OK 74076 | Oil & Gas Operator | Dec 1986 |
| 18048 | Marina Pacifica Oil Company | | Oil & Gas Operator | Dec 1981 |
| 18049 | Marine Cont. & Supply Inc. | | Oil & Gas Operator | Nov 1985 |
| 18050 | Marine Properties, Inc. | | Oil & Gas Operator | Feb 1995 |
| 18051 | Mariner Energy, Inc. | Houston, TX 77042 | Oil & Gas Operator | Nov 2010 |
| 18052 | Marino, Charles B. | Tomball, TX 77377 | Oil & Gas Operator | Jul 2025 |
| 18053 | Marion Corporation | | Oil & Gas Operator | Jan 2001 |
| 18054 | Marion County Prod. Co., L.L.C. | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 18055 | Marion Energy Inc | Houston, TX 770082292 | Oil & Gas Operator | May 2015 |
| 18056 | Marion Operating Corp | Marion, OH 43301 | Oil & Gas Operator | Dec 2020 |
| 18057 | Mariposa Petroleum Co. | | Gas Operator | Dec 1980 |
| 18058 | Maritech Resources, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Nov 2009 |
| 18059 | Maritech Resources, LLC | | Oil & Gas Operator | May 2011 |
| 18060 | Marjac Energy Co | Bremen, OH 43107 | Oil & Gas Operator | Dec 1986 |
| 18061 | Marjac Oil Company, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2025 |
| 18062 | Marjo Incorporat | | Oil & Gas Operator | Jun 1990 |
| 18063 | Marjo Oil Company | Lockhart, TX 78644 | Oil & Gas Operator | Oct 1999 |
| 18064 | Marjo Operating Company Inc | Tulsa, OK 741010729 | Oil & Gas Operator | Apr 2025 |
| 18065 | Marjo Operating Mid-Continent LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2025 |
| 18066 | Marjo, Inc. | | Oil & Gas Operator | Sep 1991 |
| 18067 | Mark & Troy Johnson | Sugar Grove, PA 16350-5938 | Oil Operator | Dec 2024 |
| 18068 | Mark A & Michael J Midlik | Warren, PA 16365-2029 | Oil & Gas Operator | Dec 2015 |
| 18069 | Mark A Meier Dba MSC Oil And Gas Co | Oklahoma City, OK 73105 | Oil & Gas Operator | May 2025 |
| 18070 | Mark F Preddy & Associates,Inc | | Oil & Gas Operator | Dec 1987 |
| 18071 | Mark Holloway Inc | Oklahoma City, OK 73107-6526 | Oil & Gas Operator | Apr 2025 |
| 18072 | Mark I Oil Company | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 18073 | Mark III Oil, Inc. | Wichita, KS 67206 | Oil Operator | Dec 2009 |
| 18074 | Mark IV Energy | San Antonio, TX 78213 | Oil & Gas Operator | Apr 1993 |
| 18075 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | May 2025 |
| 18076 | Mark Oil, Inc. | Chanute, KS 66720 | Oil Operator | Feb 2025 |
| 18077 | Mark Petroleum Inc | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2018 |
| 18078 | Mark Producing, Inc. | Houston, TX 77057 | Oil & Gas Operator | Dec 1987 |
| 18079 | Mark Resources Corp | Pittsburgh, PA 15276 | Oil & Gas Operator | Dec 1993 |
| 18080 | Mark Seifer | | Oil & Gas Operator | Dec 2024 |
| 18081 | Mark T. Kellner Oil Co. | Olean, NY 14760 | Oil & Gas Operator | Dec 2024 |
| 18082 | Mark V Petroleum Company | | Oil & Gas Operator | Feb 2020 |
| 18083 | Markan Oil Incor | | Oil Operator | Mar 1991 |
| 18084 | Markay Oil & Gas Company | Midland, TX 79701 | Oil & Gas Operator | Sep 1998 |
| 18085 | Marker Oil Compa | | Oil Operator | Jul 1985 |
| 18086 | Market Street Energy, Inc. | Flatonia, TX 78941 | Oil & Gas Operator | Jul 2025 |
| 18087 | Markham, Charles A., Jr. & Janet E. | Gowanda, NY 14070 | Gas Operator | Dec 2024 |
| 18088 | Markley Exploration | Bixby, OK 74008-5332 | Oil & Gas Operator | Jan 2014 |
| 18089 | Markley L C Corporation | Fletcher, OK 73541 | Oil & Gas Operator | Aug 2002 |
| 18090 | Marks & Co., Inc. | | Oil & Gas Operator | Dec 2021 |
| 18091 | Marks And Garner Production LTD Co | Hobbs, NM 88241 | Oil & Gas Operator | Sep 2010 |
| 18092 | Marks Operating LLC | | Oil & Gas Operator | Jul 2016 |
| 18093 | Marksmen Energy USA Inc | Worthington, OH 43085-1270 | Oil Operator | Dec 2023 |
| 18094 | Markus Production | Littleton, CO 80123 | Oil & Gas Operator | Jun 2025 |
| 18095 | Markus Production, Inc | | Oil & Gas Operator | Mar 2021 |
| 18096 | Markwest Resources Inc | Englewood, CO 801125004 | Oil & Gas Operator | Jun 2003 |
| 18097 | Marlan Anderson | | Oil Operator | Jan 2025 |
| 18098 | Marler Philip | Purcell, OK 73080-1522 | Oil & Gas Operator | Nov 2016 |
| 18099 | Marlin And Davis | | Oil Operator | Sep 1987 |
| 18100 | Marlin Coastal, L.L.C. | | Oil & Gas Operator | Apr 2008 |