| 20701 | Oklahoma Basic Economy Corp | Houston, TX 77002-6003 | Oil & Gas Operator | Apr 2020 |
| 20702 | Oklahoma Cellulose Inc | Cleveland, OK 74020 | Oil Operator | Jun 2026 |
| 20703 | Oklahoma Crude Inc | Morris, OK 74445 | Oil & Gas Operator | May 2026 |
| 20704 | Oklahoma Crude Reclaimers, LLC | | Oil Operator | Jul 2026 |
| 20705 | Oklahoma Ea II, L.L.C. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2004 |
| 20706 | Oklahoma Energy & Exploration, Inc. | Tulsa, OK 74114 | Oil Operator | Jan 1996 |
| 20707 | Oklahoma Energy Acquisitions LP | Houston, TX 77094-1900 | Oil & Gas Operator | Jun 2026 |
| 20708 | Oklahoma Energy Exchange LLC | Duncan, OK 73534-1105 | Oil & Gas Operator | Sep 2012 |
| 20709 | Oklahoma Energy LLC | Skiatook, OK 74070-3998 | Oil Operator | Apr 2025 |
| 20710 | Oklahoma Equipment & Salvage | Oklahoma City, OK 73120-5903 | Oil & Gas Operator | Mar 2015 |
| 20711 | Oklahoma Gas & Oil Corporation | Okemah, OK 74859-2224 | Oil Operator | Jun 2026 |
| 20712 | Oklahoma Liquid Resources Inc | Collinsville, OK 74021 | Oil & Gas Operator | Jun 2026 |
| 20713 | Oklahoma Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Feb 2020 |
| 20714 | Oklahoma Natural Resources Inc | Woodward, OK 73801 | Oil & Gas Operator | Sep 1996 |
| 20715 | Oklahoma O & G Royalties Inc | Duncan, OK 73533 | Oil & Gas Operator | Nov 2000 |
| 20716 | Oklahoma Oil & Gas MGMT Inc | Edmond, OK 73083-6786 | Oil & Gas Operator | Jun 2026 |
| 20717 | Oklahoma Oil And Gas Resources LLC | Guthrie, OK 73044-8095 | Oil & Gas Operator | Jul 2026 |
| 20718 | Oklahoma Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Aug 2013 |
| 20719 | Oklahoma Oil Tactics Inc | Edmond, OK 73003-1351 | Oil & Gas Operator | Mar 2015 |
| 20720 | Oklahoma Operating Company | Midland, TX 79708 | Oil & Gas Operator | Sep 2026 |
| 20721 | Oklahoma Operating, LLC | Holliday, TX 76366 | Oil Operator | Nov 2003 |
| 20722 | Oklahoma Petroleum MGMT Corp | Tulsa, OK 74119 | Oil & Gas Operator | Jun 1993 |
| 20723 | Oklahoma Prime Energy LLC | Ardmore, OK 73401 | Oil Operator | May 2020 |
| 20724 | Oklahoma Prod & Exp Co | Broken Arrow, OK 74012 | Oil & Gas Operator | May 2013 |
| 20725 | Oklahoma RB Operating Company | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 20726 | Oklahoma Rig & Salvage Inc | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2015 |
| 20727 | Oklahoma SWD Systems Inc | Odessa, TX 79762-8132 | Oil & Gas Operator | Jun 2026 |
| 20728 | Oklahoma Tank Service Inc | Oklahoma City, OK 73143 | Oil Operator | Aug 1997 |
| 20729 | Okland Oil Company | Oklahoma City, OK 73102-9022 | Oil & Gas Operator | Jul 2026 |
| 20730 | Oklaoleum Oil And Gas Inc | Bristow, OK 74010-0057 | Oil Operator | Jan 2016 |
| 20731 | Oklatex Energy, Inc. | Beaumont, TX 77702 | Oil Operator | Sep 2026 |
| 20732 | Okmar Oil Compan | | Oil & Gas Operator | Feb 1995 |
| 20733 | Okmar Oil Company | Marietta, OH 45750 | Oil & Gas Operator | Jun 2005 |
| 20734 | Okreek Oil Company | Weatherford, TX 76086 | Oil & Gas Operator | Sep 2026 |
| 20735 | Okt Petroleum Company Inc | Oklahoma City, OK 73118-7425 | Oil & Gas Operator | Oct 2013 |
| 20736 | Okt Resources, LLC | Edmond, OK 73013 | Oil & Gas Operator | Sep 2026 |
| 20737 | Oktex Operating LLC | Edmond, OK 73013-1961 | Oil & Gas Operator | May 2020 |
| 20738 | Oky Investments, Inc. | Edmond, OK 73013 | Oil & Gas Operator | Sep 2021 |
| 20739 | Ol' Boys Operations LLC | Pampa, TX 79065 | Oil & Gas Operator | Sep 2026 |
| 20740 | Ol' Oily LLC | | Oil Operator | May 2026 |
| 20741 | Old Acres Farm, Inc. | Perry, NY 14530 | Gas Operator | Dec 2025 |
| 20742 | Old Cedron, L.L.C. | Lubbock, TX 79410 | Oil & Gas Operator | May 2004 |
| 20743 | Old Chief Oil, LLC | San Antonio, TX 78205 | Oil Operator | Sep 2026 |
| 20744 | Old Dominion Oil Corporation | Oklahoma City, OK 73107 | Oil & Gas Operator | Apr 2009 |
| 20745 | Old Field Associates | | Oil & Gas Operator | Jul 2026 |
| 20746 | Old Legacy Partners LP | Wetumka, OK 74883 | Oil Operator | Jun 2026 |
| 20747 | Old MTN Gas Co Inc | Pleasantville, PA 16341-0329 | Oil & Gas Operator | Dec 2020 |
| 20748 | Old Pine Energy Corporation | Austin, TX 78755 | Oil Operator | Sep 2026 |
| 20749 | Old South Oil LLC | Marietta, OH 45750 | Oil & Gas Operator | Dec 2025 |
| 20750 | Old Timers Oil | Saratoga, TX 77585 | Oil & Gas Operator | Nov 2014 |
| 20751 | Old Timers Oil Company, LLC | Saratoga, TX 77585 | Oil Operator | Aug 2022 |
| 20752 | Old Timers Oil No. 2 Incorporated | Saratoga, TX 77585 | Oil Operator | Sep 2026 |
| 20753 | Old Union Operating Company | Austin, TX 78716 | Oil & Gas Operator | Sep 2026 |
| 20754 | Olde Chautauqua Farms | Portland, NY 14769 | Gas Operator | Dec 2025 |
| 20755 | Older Than Dirt LLC | Weatherford, TX 76086 | Oil & Gas Operator | Sep 2026 |
| 20756 | Oldfield Acquisition LP | Austin, TX 78733 | Oil & Gas Operator | Sep 1996 |
| 20757 | Oldfield Operating Corporation | | Oil Operator | Dec 2013 |
| 20758 | Olds Oil Company | Casper, WY 82604 | Oil Operator | Jun 1988 |
| 20759 | Ole Chaparral On Possum Kingdom | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 1997 |
| 20760 | Ole Crow Operating | Wichita Falls, TX 76308 | Oil Operator | Jul 2026 |
| 20761 | Ole Miss Oil & Gas Inc | New Bremen, OH 45689 | Oil & Gas Operator | Dec 1985 |
| 20762 | Ole, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 20763 | Oleksandr Antonyuk | | Oil & Gas Operator | Dec 2018 |
| 20764 | Olenox Corp. | Austin, TX 78746 | Oil Operator | Sep 2026 |
| 20765 | Oleum Energy LLC | Georgetown, TX 78628 | Oil & Gas Operator | Apr 2026 |
| 20766 | Oleum Exploration, LLC | Brodheadsvill, PA 18322 | Oil & Gas Operator | Mar 2023 |
| 20767 | Oleum Inc | | Oil & Gas Operator | Mar 1996 |
| 20768 | Oleum Incorporat | | Gas Operator | Dec 1990 |
| 20769 | Oleum Operating Company, L.C. | Longview, TX 75606 | Oil & Gas Operator | Dec 2021 |
| 20770 | Oleum Operating La LLC | | Oil & Gas Operator | Nov 2022 |
| 20771 | Oleum Partners, LLC | Frisco, TX 75034 | Oil & Gas Operator | Sep 2026 |
| 20772 | Olia Oil & Gas Services LLC | Cedar Park, TX 78630-2049 | Oil & Gas Operator | Aug 2022 |
| 20773 | Oliditt Corporation | | Gas Operator | Mar 2022 |
| 20774 | Oliditt Production Inc. | | Gas Operator | Sep 1998 |
| 20775 | Olifant Energy LLC | Tulsa, OK 74119 | Oil & Gas Operator | Jun 2019 |
| 20776 | Olipdp II, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Sep 2026 |
| 20777 | Oliphant Gertrud | Holdenville, OK 74848-0849 | Oil Operator | Aug 2013 |
| 20778 | Oliphant Operating Co,LTD,LLC | | Oil Operator | Jun 2026 |
| 20779 | Olive Oil & Gas Inc | Jennings, OK 74052 | Oil & Gas Operator | Apr 2026 |
| 20780 | Oliver Oil & Gas | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 20781 | Olmos Partners, Inc. | Boerne, TX 78006 | Oil & Gas Operator | Sep 2026 |
| 20782 | Olney Oil LLC | Boerne, TX 78006 | Oil Operator | Sep 2026 |
| 20783 | Olney Properties, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Sep 2003 |
| 20784 | Olsan Brothers, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Apr 1994 |
| 20785 | Olsen Energy Inc. | Boerne, TX 78006 | Oil & Gas Operator | Sep 2026 |
| 20786 | Olson D Producti | | Oil Operator | Jul 1994 |
| 20787 | Olson, S. A. | Kenedy, TX 78119 | Oil & Gas Operator | Aug 1994 |
| 20788 | Olson-Anderson Lease | | Oil Operator | Mar 2018 |
| 20789 | Oltex Production | Idalou, TX 79329 | Oil & Gas Operator | Sep 2026 |
| 20790 | Olympia Oil Inc | Edmond, OK 73083-7088 | Oil & Gas Operator | Jul 2020 |
| 20791 | Olympic Exploration & Production Co | Norman, OK 73072 | Oil Operator | May 2003 |
| 20792 | Olympic Exploration Inc | Denver, CO 80202 | Oil & Gas Operator | Jul 2004 |
| 20793 | Olympic Natural Gas Company | | Oil & Gas Operator | Oct 1990 |
| 20794 | Olympic Oil & Gas Co., Inc. | | Oil Operator | Apr 1991 |
| 20795 | Olympic Oil, Inc. | Hutchinson, KS 67502 | Oil & Gas Operator | May 2026 |
| 20796 | Olympic Petroleu | | Oil & Gas Operator | Jul 1993 |
| 20797 | Olympic Petroleum Co | Tulsa, OK 74114 | Oil & Gas Operator | Jun 1998 |
| 20798 | Olympic Production Company | | Oil & Gas Operator | Jul 1994 |
| 20799 | Olympic Resources Co | Wooster, OH 44691 | Oil & Gas Operator | Dec 2000 |
| 20800 | Olympus Energy, LLC | Canonsburg, PA 15317-7536 | Gas Operator | Jun 2025 |