| 20901 | Oringderff, Alma Oil Properties | Dallas, TX 75225 | Oil & Gas Operator | Mar 2012 |
| 20902 | Oriole Operating LLC | Wichita Falls, TX 76308 | Oil Operator | Sep 2026 |
| 20903 | Orion Energen Inc. | Austin, TX 78731 | Oil & Gas Operator | Jul 2023 |
| 20904 | Orion Energy Corp | MT Vernon, IL 62864 | Oil & Gas Operator | Dec 1984 |
| 20905 | Orion Energy Partners LP | Denver, CO 80202 | Oil & Gas Operator | Nov 2010 |
| 20906 | Orion Exploration LLC | Tulsa, OK 74105-5153 | Oil & Gas Operator | Apr 2015 |
| 20907 | Orion Exploration Partners LLC | Tulsa, OK 74105-5153 | Oil & Gas Operator | Nov 2025 |
| 20908 | Orion Oil & Gas Prop | Roswell, NM 88202 | Oil & Gas Operator | Apr 1998 |
| 20909 | Orion Oil & Gas Properties | Amarillo, TX 79109 | Gas Operator | Oct 2000 |
| 20910 | Orion Oil & Gas, LLC | Houston, TX 77042 | Oil & Gas Operator | Oct 2007 |
| 20911 | Orion Oil And Gas Corporation | Houston, TX 77082 | Oil & Gas Operator | Sep 2026 |
| 20912 | Orion Petro Corp | MT Vernon, IL 62864 | Oil & Gas Operator | Dec 2016 |
| 20913 | Orisol Oil Co. | Houston, TX 77206 | Oil Operator | Jun 2000 |
| 20914 | Orla Petco Inc & Hopi Drilling Co | Midland, TX 79702 | Oil Operator | Sep 2004 |
| 20915 | Orla Petco, Inc. | Midland, TX 79708 | Oil & Gas Operator | Sep 2026 |
| 20916 | Orland Oil & Gas LLC | FT Lauderdale, FL 33305 | Oil Operator | Aug 2024 |
| 20917 | Orleans Exploration Co., Inc. | | Oil & Gas Operator | Aug 1990 |
| 20918 | Orloski John C | Bartlesville, OK 74006 | Oil & Gas Operator | Jun 2025 |
| 20919 | Ormand, Don R. | Midland, TX 79705 | Oil & Gas Operator | Jan 2016 |
| 20920 | Oro Negro Inc. | | Oil & Gas Operator | Dec 2004 |
| 20921 | Oro Resources, LLC | Houston, TX 77024 | Oil & Gas Operator | Sep 2026 |
| 20922 | Oro Royalties Operating, LLC | Andrews, TX 79714 | Oil Operator | Sep 2026 |
| 20923 | Orr Jr., Donald R. | Batavia, NY 14020 | Gas Operator | Dec 2025 |
| 20924 | Orr Production Company | Austin, TX 78746 | Oil & Gas Operator | Dec 2000 |
| 20925 | Orr Robert W Jr | Zanesville, OH 43702-2683 | Oil & Gas Operator | Dec 2023 |
| 20926 | Orsburn, Wade Inc. | Gainesville, TX 76240 | Oil & Gas Operator | Nov 2002 |
| 20927 | Orson Leasing & Supply | Rockdale, TX 76567 | Oil & Gas Operator | Dec 2006 |
| 20928 | Orth Oil Company, Inc. | Cisco, TX 76437 | Oil & Gas Operator | Sep 2026 |
| 20929 | Orville S Slaughter Jr | Denver, CO 80205 | Oil & Gas Operator | Aug 2000 |
| 20930 | Orwig Oil Company Inc | Bradenton, FL 34212 | Oil & Gas Operator | Dec 2022 |
| 20931 | Orx Resources, Inc. | | Oil & Gas Operator | Dec 2009 |
| 20932 | Orx Resources, L.L.C. | Houston, TX 77067 | Oil & Gas Operator | Sep 2026 |
| 20933 | Oryx Energy Comp | | Oil & Gas Operator | Apr 1991 |
| 20934 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |
| 20935 | Os&S Operating Inc. | Electra, TX 76360 | Oil & Gas Operator | Sep 2026 |
| 20936 | Osa Oil & Gas LLC | Tulsa, OK 74131 | Oil & Gas Operator | Aug 2023 |
| 20937 | Osage Energy Resources LLC | Bartlesville, OK 74005-2527 | Oil & Gas Operator | May 2026 |
| 20938 | Osage Energy, LLC | Colony, KS 66015 | Oil Operator | Nov 2025 |
| 20939 | Osage Exploration & Development Inc | San Diego, CA 92131-3807 | Oil & Gas Operator | Oct 2016 |
| 20940 | Osage Hot Oil Service | Newcastle, WY 82701 | Oil & Gas Operator | Jul 1997 |
| 20941 | Osage Oil & Transportation Inc | Cleveland, OK 74020 | Oil & Gas Operator | Nov 2000 |
| 20942 | Osage Operating Company LLC | Seattle, WA 98133 | Oil Operator | May 2006 |
| 20943 | Osage Partners LLC | | Oil & Gas Operator | Jul 2026 |
| 20944 | Osage Petroleum Corporation | Saint Louis, MO 63131-4691 | Oil & Gas Operator | Mar 2009 |
| 20945 | Osage Resources, LLC | Wichita, KS 67202 | Oil & Gas Operator | Dec 2025 |
| 20946 | Osair Inc | Mentor, OH 44061 | Oil & Gas Operator | Dec 2021 |
| 20947 | Osborn Energy, LLC | Bucyrus, KS 66013 | Oil & Gas Operator | Jul 2017 |
| 20948 | Osborn Heirs Co | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2026 |
| 20949 | Osborn Heirs Com | | Oil & Gas Operator | May 1995 |
| 20950 | Osborn Heirs Company LTD | San Antonio, TX 78217 | Oil & Gas Operator | Apr 2026 |
| 20951 | Osborn Oil & Gas | | Oil & Gas Operator | Jun 1991 |
| 20952 | Osborn,W.B. Oil & Gas Operations | San Antonio, TX 78217 | Oil & Gas Operator | Sep 2026 |
| 20953 | Osborne Oil & Gas, LLC | Hueysville, KY 41640 | Oil & Gas Operator | Dec 2024 |
| 20954 | Osborne Oil Co. | Dallas, TX 75244 | Oil & Gas Operator | Aug 2003 |
| 20955 | Osburn Gerald Dba Ozzy & Son Oil & Gas | Drumright, OK 74030-5467 | Oil Operator | Oct 2020 |
| 20956 | Oscar Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Sep 2004 |
| 20957 | Oscar'S Well Service Inc | Okemah, OK 74859 | Oil & Gas Operator | Apr 1998 |
| 20958 | Osceola Oil & Gas Corporation | Somerset, TX 78069 | Oil & Gas Operator | Aug 1994 |
| 20959 | Osci Oil And Gas, Inc. | Parker, KS 66072 | Oil Operator | Jun 1998 |
| 20960 | Oshtah Oil Company LLC | Stratford, OK 74872 | Oil & Gas Operator | Sep 2018 |
| 20961 | Osman Global Services LLC | | Oil & Gas Operator | Jan 2025 |
| 20962 | Oso Exploration & Production, LLC | Houston, TX 77269 | Oil Operator | Sep 2026 |
| 20963 | Oso Exploration Co. | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2011 |
| 20964 | Oso Oil & Gas Properties LLC | Price, UT 84501 | Gas Operator | Jun 2016 |
| 20965 | Oso Perdido Services LLC | Flatonia, TX 78941 | Oil Operator | Jun 2026 |
| 20966 | Oso Resources LLC | Edmond, OK 73003 | Oil & Gas Operator | May 2026 |
| 20967 | Ososki Edward D Dba Federal Oil Company | | Oil & Gas Operator | Jul 2026 |
| 20968 | Osprey Petroleum Company, Inc. | Manvel, TX 77578 | Oil & Gas Operator | May 2020 |
| 20969 | Osr Oil & Gas Company | Victoria, TX 77902 | Oil & Gas Operator | Jul 2000 |
| 20970 | Osr Oil & Gas Corp | | Oil & Gas Operator | Dec 2024 |
| 20971 | Osterhout Phillip L | Drumright, OK 74030-0693 | Oil & Gas Operator | Jan 2014 |
| 20972 | Ostrich Oil & Gas, LLC | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 20973 | Oswego Arbuckle Enterprise Inc | S Coffeyville, OK 74072-9702 | Oil & Gas Operator | Mar 2015 |
| 20974 | Oswego Oil & Gas | | Oil & Gas Operator | Jun 1984 |
| 20975 | Oswego, Inc. | Amarillo, TX 79109 | Oil & Gas Operator | Jun 2004 |
| 20976 | Osyka Oil & Gas, Inc. | Metairie, LA 70004 | Oil & Gas Operator | Sep 2026 |
| 20977 | Osyka Permian, LLC | Houston, TX 77079 | Oil & Gas Operator | Sep 2026 |
| 20978 | Osyka Producing Company, Inc. | Houston, TX 77242 | Oil & Gas Operator | Sep 2026 |
| 20979 | Otb Operating, LLC | Stanton, TX 79782 | Oil & Gas Operator | Sep 2026 |
| 20980 | Otc Investors Inc | | Oil Operator | May 2026 |
| 20981 | Otc Petroleum Corporation | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2015 |
| 20982 | Otc/Occ Not Assigned | | Oil & Gas Operator | Dec 2024 |
| 20983 | Otex Inc | N Canton, OH 44720 | Oil & Gas Operator | Dec 1988 |
| 20984 | Otex LLC | Santa Anna, TX 76878 | Oil & Gas Operator | Sep 2026 |
| 20985 | Otex Resources LLC | Baytown, TX 77520 | Oil & Gas Operator | Sep 2026 |
| 20986 | Otis C. Coles, Jr. | | Oil & Gas Operator | Jan 1998 |
| 20987 | Oto, Co. | Woodward, OK 73802 | Oil & Gas Operator | Jun 1998 |
| 20988 | Ott Inc | Casper, WY 82602 | Oil Operator | Oct 2025 |
| 20989 | Otter Exploration Inc | Warren, PA 16365-9689 | Oil & Gas Operator | Dec 2021 |
| 20990 | Ouachita Exploration Inc | Chickasha, OK 73018 | Oil & Gas Operator | May 2026 |
| 20991 | Ouida Oil | Rowlett, TX 75030 | Oil & Gas Operator | Mar 2008 |
| 20992 | Ouida Oil Co. | | Oil & Gas Operator | Apr 1999 |
| 20993 | Outback Petroleum Inc | Moore, OK 73160-9998 | Oil & Gas Operator | Mar 2015 |
| 20994 | Outlaw Oil LLC | Caldwell, TX 77836 | Oil & Gas Operator | Sep 2026 |
| 20995 | Outlaw Well Service LLC | Hays, KS 67601 | Oil Operator | Jan 2026 |
| 20996 | Outline Oil Company LLC | Beeville, TX 78104 | Oil Operator | Sep 2026 |
| 20997 | Outline Oil Corp. | San Antonio, TX 78217 | Oil & Gas Operator | Sep 2026 |
| 20998 | Outlook Petroleum Corp. | Midland, TX 79702 | Oil & Gas Operator | Jan 2001 |
| 20999 | Outman, Joshua J. | Andover, NY 14806 | Oil & Gas Operator | Dec 2025 |
| 21000 | Output Acquisition Corp. | | Oil & Gas Operator | Jul 2010 |