| 801 | Mount Richard | Newark, OH 43055 | Oil Operator | Dec 2005 |
| 802 | Mountaineer State Operations, LLC | Sandyville, WV 25275 | Oil & Gas Operator | Dec 2025 |
| 803 | Mourning James & Carol | Middleport, OH 45760-1214 | Gas Operator | Dec 2024 |
| 804 | MS Producing LLC | Creston, OH 44217 | Oil & Gas Operator | Dec 2025 |
| 805 | Mullins Well Service | MT Gilead, OH 43338 | Oil & Gas Operator | Dec 2018 |
| 806 | Murphy Oil Company Inc | Lancaster, OH 43130 | Oil & Gas Operator | Dec 2024 |
| 807 | Murtha Contracting Inc. | Conneaut, OH 44030 | Oil & Gas Operator | Dec 2009 |
| 808 | Mutual Oil & Gas Co | Akron, OH 44311 | Oil & Gas Operator | Dec 2000 |
| 809 | Myers Drilling Company | Barboursville, WV 25504 | Oil & Gas Operator | Dec 2025 |
| 810 | N & K Oil & Gas Inc | Marietta, OH 45750 | Oil & Gas Operator | Dec 1998 |
| 811 | N & N Oil | Somerset, OH 43783 | Oil & Gas Operator | Dec 2014 |
| 812 | N Eastern Oh O&G Exp Inc | Cleveland, OH 44106 | Oil & Gas Operator | Dec 1999 |
| 813 | National Energy Exp Inc | Centerville, OH 45458-2005 | Oil & Gas Operator | Dec 2024 |
| 814 | Natland Energy Corp | New Philadelphi, OH 44663 | Oil & Gas Operator | Dec 1996 |
| 815 | NCL Natural Resources LLC | Spring, TX 77381-5261 | Oil & Gas Operator | Dec 2017 |
| 816 | Neos Energy LLC | Columbus, OH 43220-0265 | Oil & Gas Operator | Dec 2024 |
| 817 | Nethers Brothers LLC | Newark, OH 43055 | Oil & Gas Operator | Dec 2025 |
| 818 | Nethers Gary L | Newark, OH 43055 | Oil & Gas Operator | Dec 2024 |
| 819 | Nethers Oil And Gas LLC | Newark, OH 43055 | Oil Operator | Dec 2025 |
| 820 | Newstar Energy USA Inc | Thornville, OH 43076 | Oil & Gas Operator | Aug 2004 |
| 821 | NGM Noble LTD | Wooster, OH 44691 | Oil & Gas Operator | Dec 2025 |
| 822 | Ngo Development Corp. | Newark, OH 43055 | Oil & Gas Operator | Dec 2025 |
| 823 | Nieset Lawrence & Christopher | Helena, OH 43435 | Oil Operator | Dec 2025 |
| 824 | Noble Gas Co | Wooster, OH 44691 | Oil & Gas Operator | Dec 1997 |
| 825 | Noble Oil Corp | Columbus, OH 43229 | Oil & Gas Operator | Dec 1996 |
| 826 | Noble Petroleum LLC | Lower Salem, OH 45745-9648 | Oil & Gas Operator | Dec 2025 |
| 827 | North Amer Oil Exp Inc | Trenton, OH 45067 | Oil Operator | Dec 2025 |
| 828 | North Amer Petroleum Inc | Zanesville, OH 43701 | Oil & Gas Operator | Dec 2000 |
| 829 | North American Petroleum Inc | Scottsdale, AZ 85262 | Oil & Gas Operator | Dec 2025 |
| 830 | North American Prod Co | Wooster, OH 44691 | Oil & Gas Operator | Dec 1998 |
| 831 | North Coast Petroleum Inc | Hiram, OH 44234 | Oil & Gas Operator | Dec 1993 |
| 832 | North East Fuel Inc | Wooster, OH 44691 | Oil & Gas Operator | Dec 2015 |
| 833 | North Ridge Energy Inc | Rome, OH 44085-9713 | Oil & Gas Operator | Dec 2025 |
| 834 | Northeastern Energy | Warren, OH 44484 | Oil & Gas Operator | Dec 1991 |
| 835 | Northern Processors Inc | The Woodlands, TX 77387-9385 | Oil & Gas Operator | Sep 2010 |
| 836 | Northwood Energy Corp | Columbus, OH 43221 | Oil & Gas Operator | Jun 2026 |
| 837 | Nucomer Energy LLC | Erie, PA 16510 | Oil & Gas Operator | May 2026 |
| 838 | Nuttco Oil & Gas | Corning, OH 43730 | Oil & Gas Operator | Dec 2010 |
| 839 | Nytis Exploration Company LLC | Lexington, KY 40509 | Oil & Gas Operator | Dec 2021 |
| 840 | Oak Dale Drilling Co | Logan, OH 43138-1851 | Oil & Gas Operator | Dec 2015 |
| 841 | Obermiller Clarence Trust | Creston, OH 44217 | Oil & Gas Operator | Dec 1987 |
| 842 | Obermiller Paul J | Creston, OH 44217 | Oil & Gas Operator | Dec 2014 |
| 843 | Og Co., Inc. | Houston, TX 77057 | Oil & Gas Operator | Sep 2026 |
| 844 | Ohio Energy Assets, Inc. | Laurelville, OH 43135 | Oil & Gas Operator | Dec 2014 |
| 845 | Ohio Energy Group Inc | Uniontown, OH 44685 | Oil & Gas Operator | Dec 1988 |
| 846 | Ohio Energy Operators LLC | Colorado Spring, CO 80908 | Oil Operator | Dec 2018 |
| 847 | Ohio L & M Company Inc | Marietta, OH 45750 | Oil & Gas Operator | Dec 2008 |
| 848 | Ohio Natural Fuel Co | Canton, OH 44718 | Oil & Gas Operator | Dec 1985 |
| 849 | Ohio Oil & Gas | Fowler, OH 44418 | Oil & Gas Operator | Dec 1988 |
| 850 | Ohio Production Corp | Westerville, OH 43081 | Oil & Gas Operator | Dec 2001 |
| 851 | Ohio Production* | Newark, OH 43055 | Oil & Gas Operator | Dec 1987 |
| 852 | Ohio Valley Energy Systems Corp | Austintown, OH 44515 | Oil & Gas Operator | Dec 2025 |
| 853 | Oil & Gas Solutions LTD | Wooster, OH 44691 | Oil & Gas Operator | Dec 2007 |
| 854 | Oil & Realty Devlop Inc | Columbus, OH 43212 | Oil Operator | Dec 1986 |
| 855 | Oil Enterprises | Logan, OH 43138 | Oil & Gas Operator | Dec 2025 |
| 856 | Oil Search Inc | Brookfield, OH 44403 | Oil & Gas Operator | Dec 2025 |
| 857 | Oiltech Inc | Yuba City, CA 95991 | Oil & Gas Operator | Dec 1984 |
| 858 | Oiltex, Inc. | Baltimore, MD 21221 | Oil & Gas Operator | Dec 2013 |
| 859 | Okmar Oil Company | Marietta, OH 45750 | Oil & Gas Operator | Jun 2005 |
| 860 | Old South Oil LLC | Marietta, OH 45750 | Oil & Gas Operator | Dec 2025 |
| 861 | Ole Miss Oil & Gas Inc | New Bremen, OH 45689 | Oil & Gas Operator | Dec 1985 |
| 862 | Olympic Resources Co | Wooster, OH 44691 | Oil & Gas Operator | Dec 2000 |
| 863 | Omac Oil & Gas Co | Newark, OH 43055 | Oil & Gas Operator | Dec 1990 |
| 864 | Omega Oil Corp | Lafayette, IN 47903 | Oil & Gas Operator | Dec 1987 |
| 865 | Orion Energy Corp | MT Vernon, IL 62864 | Oil & Gas Operator | Dec 1984 |
| 866 | Orion Petro Corp | MT Vernon, IL 62864 | Oil & Gas Operator | Dec 2016 |
| 867 | Orr Robert W Jr | Zanesville, OH 43702-2683 | Oil & Gas Operator | Dec 2023 |
| 868 | Orwig Oil Company Inc | Bradenton, FL 34212 | Oil & Gas Operator | Dec 2022 |
| 869 | Osair Inc | Mentor, OH 44061 | Oil & Gas Operator | Dec 2021 |
| 870 | Otex Inc | N Canton, OH 44720 | Oil & Gas Operator | Dec 1988 |
| 871 | Ows Acquisition Co LLC | Louisville, OH 44641 | Oil & Gas Operator | Dec 2025 |
| 872 | Oxford Oil | Zanesville, OH 43702 | Oil & Gas Operator | Dec 2012 |
| 873 | Ozark Oil LLC | Beallsville, OH 43716 | Oil & Gas Operator | Dec 2025 |
| 874 | P & D Valentine Oil Co | New Matamoras, OH 45767 | Oil & Gas Operator | Dec 2018 |
| 875 | P & S Energy Inc | Mineral Ridge, OH 44440 | Oil & Gas Operator | Dec 2019 |
| 876 | P & S Production LLC | Ravenna, OH 44266 | Oil & Gas Operator | Dec 2013 |
| 877 | P P & G Oil | Pickerington, OH 43147 | Oil & Gas Operator | Dec 2024 |
| 878 | P. D. L. Services, Inc. | Minerva, OH 44657 | Oil & Gas Operator | Dec 2024 |
| 879 | Pac Drilling LLC | Bolivar, OH 44612 | Oil & Gas Operator | Dec 2025 |
| 880 | Pace Co/Chas E Hall | Marietta, OH 45750 | Oil & Gas Operator | Dec 1990 |
| 881 | Parker Hannifin Corporation | Ravenna, OH 44266 | Oil & Gas Operator | Dec 2025 |
| 882 | Parkside Pet Of Ohio Inc | Granville, OH 43023 | Oil & Gas Operator | Dec 1987 |
| 883 | Paroco DRLG Funds Inc | Houston, TX 77002 | Oil & Gas Operator | Dec 1993 |
| 884 | Parrot Energy Company | Cortland, OH 44410 | Oil & Gas Operator | Dec 2025 |
| 885 | Partners Petroleum Inc | Independence, OH 44131 | Oil & Gas Operator | Dec 1988 |
| 886 | Paw Oil And Gas LTD | North Canton, OH 44720 | Oil & Gas Operator | Dec 2024 |
| 887 | PD Valentine Oil & Gas LLC | Newport, OH 45768 | Oil & Gas Operator | Dec 2025 |
| 888 | PDC Energy Inc | Denver, CO 80203 | Oil & Gas Operator | May 2026 |
| 889 | PDQ Oil & Gas LLC | The Plains, OH 45780 | Oil & Gas Operator | Dec 2025 |
| 890 | Pedgeco Inc | Cleveland, OH 44115 | Oil & Gas Operator | Dec 1984 |
| 891 | Pelican Producing Inc | Caldwell, OH 43724 | Oil & Gas Operator | Dec 1996 |
| 892 | Pemco Gas Inc | Indian Harbor B, FL 32937 | Oil & Gas Operator | Dec 1997 |
| 893 | Peninsula Group Inc | Peninsula, OH 44264 | Oil & Gas Operator | Dec 1991 |
| 894 | Peninsular Oil & Gas Co | Ada, MI 49301 | Oil & Gas Operator | Dec 2001 |
| 895 | Penn-Ohio Investment Corp. | New Philadelphi, OH 44663 | Oil & Gas Operator | Dec 2004 |
| 896 | Pennenergy Resources LLC | Pittsburgh, PA 15275-1063 | Oil & Gas Operator | Jun 2026 |
| 897 | Pennzenergy | Houston, TX 77252 | Oil & Gas Operator | Dec 1986 |
| 898 | Pep Drilling LLC | MT Vernon, IL 62864 | Oil & Gas Operator | Dec 2025 |
| 899 | Pepper Oil Co | Newark, OH 43055 | Oil & Gas Operator | Dec 1992 |
| 900 | Peroco Oil & Gas | Killbuck, OH 44637 | Oil & Gas Operator | Dec 1987 |