| 21801 | Ok Oil Company, Inc. | Bivins, TX 75555 | Oil & Gas Operator | Feb 2013 |
| 21802 | Ok Operating Co | Midland, TX 79702 | Oil & Gas Operator | Aug 1999 |
| 21803 | Ok-La-Tex Production, Inc. | | Oil & Gas Operator | Jan 1982 |
| 21804 | Okc Energy Corporation | Oklahoma City, OK 73120-3119 | Oil & Gas Operator | Nov 2014 |
| 21805 | Okemah Production Inc | | Oil Operator | Dec 2005 |
| 21806 | Okie Crude Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2025 |
| 21807 | Okie Oil Inc | Sapulpa, OK 74067-0290 | Oil & Gas Operator | Mar 2011 |
| 21808 | Okie Operating Company, LTD. | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2026 |
| 21809 | Okkatahula, Inc. | | Oil Operator | Nov 1978 |
| 21810 | Okla Sub-Surface Pump & Supply Co | Seminole, OK 74804 | Oil & Gas Operator | Sep 2024 |
| 21811 | Okla. Magic Circle Energy Corp. | Shawnee, OK 74801 | Oil & Gas Operator | Jul 2004 |
| 21812 | Oklahoma Arrowhead Energy, Inc. | Nichols Hill, OK 73116 | Oil & Gas Operator | Sep 1996 |
| 21813 | Oklahoma Basic Economy Corp | Houston, TX 77002-6003 | Oil & Gas Operator | Apr 2020 |
| 21814 | Oklahoma Cellulose Inc | Cleveland, OK 74020 | Oil Operator | Nov 2025 |
| 21815 | Oklahoma Crude Inc | Morris, OK 74445 | Oil & Gas Operator | Nov 2025 |
| 21816 | Oklahoma Crude Reclaimers, LLC | | Oil Operator | Dec 2025 |
| 21817 | Oklahoma Drilling Corporation | | Oil & Gas Operator | Sep 1994 |
| 21818 | Oklahoma Ea II, L.L.C. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2004 |
| 21819 | Oklahoma Energy & Exploration, Inc. | Tulsa, OK 74114 | Oil Operator | Jan 1996 |
| 21820 | Oklahoma Energy Acquisitions LP | Houston, TX 77094-1900 | Oil & Gas Operator | Nov 2025 |
| 21821 | Oklahoma Energy Exchange LLC | Duncan, OK 73534-1105 | Oil & Gas Operator | Sep 2012 |
| 21822 | Oklahoma Energy LLC | Skiatook, OK 74070-3998 | Oil Operator | Apr 2025 |
| 21823 | Oklahoma Equipment & Salvage | Oklahoma City, OK 73120-5903 | Oil & Gas Operator | Mar 2015 |
| 21824 | Oklahoma Gas & Oil Corp | | Oil Operator | Oct 2018 |
| 21825 | Oklahoma Liquid Resources Inc | Collinsville, OK 74021 | Oil & Gas Operator | Oct 2025 |
| 21826 | Oklahoma Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Feb 2020 |
| 21827 | Oklahoma Natural Resources Inc | Woodward, OK 73801 | Oil & Gas Operator | Sep 1996 |
| 21828 | Oklahoma O & G Royalties Inc | Duncan, OK 73533 | Oil & Gas Operator | Nov 2000 |
| 21829 | Oklahoma Oil & Gas MGMT Inc | Edmond, OK 73083-6786 | Oil & Gas Operator | Nov 2025 |
| 21830 | Oklahoma Oil And Gas Resources LLC | Guthrie, OK 73044-8095 | Oil & Gas Operator | Dec 2025 |
| 21831 | Oklahoma Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Aug 2013 |
| 21832 | Oklahoma Oil Tactics Inc | Edmond, OK 73003-1351 | Oil & Gas Operator | Mar 2015 |
| 21833 | Oklahoma Operating Company | Midland, TX 79708 | Oil & Gas Operator | Feb 2026 |
| 21834 | Oklahoma Operating, LLC | Holliday, TX 76366 | Oil Operator | Nov 2003 |
| 21835 | Oklahoma Petroleum MGMT Corp | Tulsa, OK 74119 | Oil & Gas Operator | Jun 1993 |
| 21836 | Oklahoma Plugging & Equip Inc | | Oil & Gas Operator | Nov 2000 |
| 21837 | Oklahoma Prime Energy LLC | Ardmore, OK 73401 | Oil Operator | May 2020 |
| 21838 | Oklahoma Prod & Exp Co | Broken Arrow, OK 74012 | Oil & Gas Operator | May 2013 |
| 21839 | Oklahoma RB Operating Company | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 21840 | Oklahoma Rig & Salvage Inc | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2015 |
| 21841 | Oklahoma Sterling Oil & Gas Corp | Tulsa, OK 74170 | Oil & Gas Operator | Jun 1997 |
| 21842 | Oklahoma SWD Systems Inc | Odessa, TX 79762-8132 | Oil & Gas Operator | Oct 2025 |
| 21843 | Oklahoma Tank Service Inc | Oklahoma City, OK 73143 | Oil Operator | Aug 1997 |
| 21844 | Okland Development Corp | Tulsa, OK 74104 | Oil & Gas Operator | Nov 1996 |
| 21845 | Okland Oil Company | Oklahoma City, OK 73102-9022 | Oil & Gas Operator | Dec 2025 |
| 21846 | Oklaoleum Oil And Gas Inc | Bristow, OK 74010-0057 | Oil Operator | Jan 2016 |
| 21847 | Oklatex Energy, Inc. | Beaumont, TX 77702 | Oil Operator | Feb 2026 |
| 21848 | Okmar Oil Compan | | Oil & Gas Operator | Feb 1995 |
| 21849 | Okmar Oil Company | Marietta, OH 45750 | Oil & Gas Operator | Jun 2005 |
| 21850 | Okreek Oil Company | Weatherford, TX 76086 | Oil & Gas Operator | Feb 2026 |
| 21851 | Okt Petroleum Company Inc | Oklahoma City, OK 73118-7425 | Oil & Gas Operator | Oct 2013 |
| 21852 | Okt Resources, LLC | Edmond, OK 73013 | Oil & Gas Operator | Feb 2026 |
| 21853 | Oktex Operating LLC | Edmond, OK 73013-1961 | Oil & Gas Operator | May 2020 |
| 21854 | Oky Investments, Inc. | Edmond, OK 73013 | Oil & Gas Operator | Sep 2021 |
| 21855 | Ol' Boys Operations LLC | Pampa, TX 79065 | Oil & Gas Operator | Feb 2026 |
| 21856 | Ol' Oily LLC | | Oil Operator | Sep 2025 |
| 21857 | Old Acres Farm, Inc. | Perry, NY 14530 | Gas Operator | Dec 2024 |
| 21858 | Old Cedron, L.L.C. | Lubbock, TX 79410 | Oil & Gas Operator | May 2004 |
| 21859 | Old Chief Oil, LLC | New Braunfels, TX 78132 | Oil Operator | Feb 2026 |
| 21860 | Old Dominion Oil Corporation | Oklahoma City, OK 73107 | Oil & Gas Operator | Apr 2009 |
| 21861 | Old Field Associates | | Oil & Gas Operator | Dec 2025 |
| 21862 | Old MTN Gas Co Inc | Pleasantville, PA 16341-0329 | Oil & Gas Operator | Dec 2020 |
| 21863 | Old Pine Energy Corporation | Austin, TX 78755 | Oil Operator | Feb 2026 |
| 21864 | Old South Oil LLC | Marietta, OH 45750 | Oil & Gas Operator | Dec 2024 |
| 21865 | Old Timers Oil | Saratoga, TX 77585 | Oil & Gas Operator | Nov 2014 |
| 21866 | Old Timers Oil Company, LLC | Saratoga, TX 77585 | Oil Operator | Aug 2022 |
| 21867 | Old Timers Oil No. 2 Incorporated | Saratoga, TX 77585 | Oil Operator | Feb 2026 |
| 21868 | Old Union Operating Company | Austin, TX 78716 | Oil & Gas Operator | Feb 2026 |
| 21869 | Olde Chautauqua Farms | Portland, NY 14769 | Gas Operator | Dec 2024 |
| 21870 | Older Than Dirt LLC | Weatherford, TX 76086 | Oil & Gas Operator | Feb 2026 |
| 21871 | Oldfield Acquisition LP | Austin, TX 78733 | Oil & Gas Operator | Sep 1996 |
| 21872 | Oldfield Operating Corporation | | Oil Operator | Dec 2013 |
| 21873 | Olds Oil Company | Casper, WY 82604 | Oil Operator | Jun 1988 |
| 21874 | Ole Chaparral On Possum Kingdom | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 1997 |
| 21875 | Ole Crow Operating | Wichita Falls, TX 76308 | Oil Operator | Nov 2025 |
| 21876 | Ole Miss Oil & Gas Inc | New Bremen, OH 45689 | Oil & Gas Operator | Dec 1985 |
| 21877 | Ole, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 21878 | Oleksandr Antonyuk | | Oil & Gas Operator | Dec 2018 |
| 21879 | Olenox Corp. | Katy, TX 77449 | Oil Operator | Feb 2026 |
| 21880 | Oleum Energy LLC | Georgetown, TX 78628 | Oil & Gas Operator | Dec 2025 |
| 21881 | Oleum Exploration, LLC | Brodheadsvill, PA 18322 | Oil & Gas Operator | Mar 2023 |
| 21882 | Oleum Inc | | Oil & Gas Operator | Mar 1996 |
| 21883 | Oleum Incorporat | | Gas Operator | Dec 1990 |
| 21884 | Oleum Operating Company, L.C. | Longview, TX 75606 | Oil & Gas Operator | Dec 2021 |
| 21885 | Oleum Operating La LLC | | Oil & Gas Operator | Nov 2022 |
| 21886 | Oleum Partners, LLC | Frisco, TX 75034 | Oil & Gas Operator | Feb 2026 |
| 21887 | Olia Oil & Gas Services LLC | Cedar Park, TX 78630-2049 | Oil & Gas Operator | Aug 2022 |
| 21888 | Oliditt Corporation | | Gas Operator | Mar 2022 |
| 21889 | Oliditt Production Inc. | | Gas Operator | Sep 1998 |
| 21890 | Olifant Energy LLC | Tulsa, OK 74119 | Oil & Gas Operator | Jun 2019 |
| 21891 | Olipdp II, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Feb 2026 |
| 21892 | Oliphant Gertrud | Holdenville, OK 74848-0849 | Oil Operator | Aug 2013 |
| 21893 | Oliphant Operating Co,LTD,LLC | | Oil Operator | Nov 2025 |
| 21894 | Olive Oil & Gas Inc | Jennings, OK 74052 | Oil & Gas Operator | Oct 2025 |
| 21895 | Oliver Oil & Gas | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |
| 21896 | Olmos Partners, Inc. | Boerne, TX 78006 | Oil & Gas Operator | Feb 2026 |
| 21897 | Olney Oil LLC | Boerne, TX 78006 | Oil Operator | Feb 2026 |
| 21898 | Olney Properties, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Sep 2003 |
| 21899 | Olsan Brothers, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Apr 1994 |
| 21900 | Olsen Energy Inc. | Boerne, TX 78006 | Oil & Gas Operator | Feb 2026 |