| 21001 | Oscar'S Well Service Inc | Okemah, OK 74859 | Oil & Gas Operator | Apr 1998 |
| 21002 | Osceola Oil & Gas Corporation | Somerset, TX 78069 | Oil & Gas Operator | Aug 1994 |
| 21003 | Osci Oil And Gas, Inc. | Parker, KS 66072 | Oil Operator | Jun 1998 |
| 21004 | Oshtah Oil Company LLC | Stratford, OK 74872 | Oil & Gas Operator | Sep 2018 |
| 21005 | Oso Exploration & Production, LLC | Houston, TX 77269 | Oil Operator | Sep 2024 |
| 21006 | Oso Exploration Co. | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2011 |
| 21007 | Oso Oil & Gas Properties LLC | Price, UT 84501 | Gas Operator | Jun 2016 |
| 21008 | Oso Resources LLC | Oklahoma City, OK 73118-5022 | Oil & Gas Operator | Jun 2024 |
| 21009 | Ososki Edward D Dba Federal Oil Company | | Oil & Gas Operator | Jun 2022 |
| 21010 | Osprey Petroleum Company, Inc. | Manvel, TX 77578 | Oil & Gas Operator | May 2020 |
| 21011 | Osr Oil & Gas Company | Victoria, TX 77902 | Oil & Gas Operator | Jul 2000 |
| 21012 | Osr Oil & Gas Corp | Midland, TX 79710 | Oil & Gas Operator | Dec 2023 |
| 21013 | Osterhout Phillip L | Drumright, OK 74030-0693 | Oil & Gas Operator | Jan 2014 |
| 21014 | Ostrich Oil & Gas, LLC | Midland, TX 79701 | Oil & Gas Operator | Sep 2024 |
| 21015 | Oswego Arbuckle Enterprise Inc | S Coffeyville, OK 74072-9702 | Oil & Gas Operator | Mar 2015 |
| 21016 | Oswego Oil & Gas | | Oil & Gas Operator | Jun 1984 |
| 21017 | Oswego, Inc. | Amarillo, TX 79109 | Oil & Gas Operator | Jun 2004 |
| 21018 | Osyka Oil & Gas, Inc. | Metairie, LA 70004 | Oil & Gas Operator | Sep 2024 |
| 21019 | Osyka Permian, LLC | Houston, TX 77079 | Oil & Gas Operator | Sep 2024 |
| 21020 | Osyka Producing Company, Inc. | Houston, TX 77242 | Oil & Gas Operator | Sep 2024 |
| 21021 | Otb Operating, LLC | Stanton, TX 79782 | Oil & Gas Operator | Sep 2024 |
| 21022 | Otc Investors Inc | Locust Grove, OK 74352 | Oil Operator | Mar 2024 |
| 21023 | Otc Petroleum Corporation | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2015 |
| 21024 | Otc/Occ Not Assigned | | Oil & Gas Operator | May 2024 |
| 21025 | Otex Inc | N Canton, OH 44720 | Oil & Gas Operator | Dec 1988 |
| 21026 | Otex LLC | Santa Anna, TX 76878 | Oil & Gas Operator | Sep 2024 |
| 21027 | Otex Resources LLC | Baytown, TX 77520 | Oil & Gas Operator | Sep 2024 |
| 21028 | Otis C. Coles, Jr. | | Oil & Gas Operator | Jan 1998 |
| 21029 | Oto, Co. | Woodward, OK 73802 | Oil & Gas Operator | Jun 1998 |
| 21030 | Ott Inc | Casper, WY 82602 | Oil Operator | Jun 2024 |
| 21031 | Otter Exploration Inc | Warren, PA 16365-9689 | Oil & Gas Operator | Dec 2021 |
| 21032 | Ouachita Exploration Inc | Chickasha, OK 73018 | Oil & Gas Operator | Jun 2024 |
| 21033 | Ouida Oil | Rowlett, TX 75030 | Oil & Gas Operator | Mar 2008 |
| 21034 | Ouida Oil Co. | | Oil & Gas Operator | Apr 1999 |
| 21035 | Outback Petroleum Inc | Moore, OK 73160-9998 | Oil & Gas Operator | Mar 2015 |
| 21036 | Outlaw Oil And Gas LLC | Kaw City, OK 74641 | Oil & Gas Operator | Jun 2024 |
| 21037 | Outlaw Oil LLC | Caldwell, TX 77836 | Oil & Gas Operator | Sep 2024 |
| 21038 | Outlaw Well Service LLC | Hays, KS 67601 | Oil Operator | Apr 2024 |
| 21039 | Outline Oil Company LLC | Beeville, TX 78104 | Oil Operator | Sep 2024 |
| 21040 | Outline Oil Corp. | San Antonio, TX 78217 | Oil & Gas Operator | Sep 2024 |
| 21041 | Outlook Petroleum Corp. | Midland, TX 79702 | Oil & Gas Operator | Jan 2001 |
| 21042 | Outman, Joshua J. | Andover, NY 14806 | Oil & Gas Operator | Dec 2023 |
| 21043 | Output Acquisition Corp. | | Oil & Gas Operator | Jul 2010 |
| 21044 | Output Exploration LLC | | Oil & Gas Operator | Dec 2006 |
| 21045 | Ouut Investing LLC | Mineral Wells, TX 76068 | Oil Operator | Mar 2020 |
| 21046 | Ovaco Energy Inc. | | Oil & Gas Operator | Nov 2009 |
| 21047 | Ovation Energy II, LP | Houston, TX 77279 | Oil & Gas Operator | Jun 2011 |
| 21048 | Ovation Energy, LP | N Richlnd HLS, TX 76180 | Oil & Gas Operator | Sep 2004 |
| 21049 | Overfield, Lee R | Waverly, KY 42462 | Oil Operator | Dec 2016 |
| 21050 | Overflow Energy Stack LLC | Booker, TX 79005 | Oil Operator | Sep 2022 |
| 21051 | Overflow Energy, LLC | Booker, TX 79005 | Oil & Gas Operator | Sep 2024 |
| 21052 | Overland Exploration Company | | Oil Operator | May 2024 |
| 21053 | Overland Investments Inc | Coweta, OK 74429 | Oil & Gas Operator | Jun 2024 |
| 21054 | Overland Operating Company, LLC | Abilene, TX 79601 | Oil Operator | Sep 2024 |
| 21055 | Overland Resources LLC | Greenwood VIllage, CO 80111 | Oil & Gas Operator | Jul 2019 |
| 21056 | Overly Operating Co. | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2013 |
| 21057 | Overstreet, Jamie L | Hondo, TX 78861 | Oil & Gas Operator | Sep 2024 |
| 21058 | Overton Park Oil & Gas LP | Fort Worth, TX 76109 | Oil & Gas Operator | Sep 2024 |
| 21059 | Ovintiv Mid-Continent Inc. | The Woodlands, TX 77380-2764 | Oil & Gas Operator | Jul 2024 |
| 21060 | Ovintiv USA Inc. | Denver, CO 80202 | Oil & Gas Operator | Sep 2024 |
| 21061 | Owco Production Co., Inc. | | Oil Operator | Aug 1997 |
| 21062 | Owen Contracting Company Inc | | Oil Operator | Apr 2007 |
| 21063 | Owen Production Co | | Oil Operator | May 2001 |
| 21064 | Owen'S Pumping Service | | Oil Operator | May 2024 |
| 21065 | Owen, Matthew | Hamilton, KS 66853 | Oil Operator | Sep 2016 |
| 21066 | Owens James W | Tulsa, OK 74114-1425 | Oil & Gas Operator | Oct 2022 |
| 21067 | Owens Oil | | Oil Operator | Dec 2000 |
| 21068 | Owens Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Sep 2008 |
| 21069 | Owens Oil Company, LLC | Yates Center, KS 66783 | Oil Operator | May 2024 |
| 21070 | Owens Pet Inc | Midland, TX 79702 | Oil & Gas Operator | Aug 1995 |
| 21071 | Owens Petroleum | | Oil Operator | May 2006 |
| 21072 | Owens Petroleum LLC | Yates Center, KS 66783 | Oil & Gas Operator | May 2024 |
| 21073 | Owens Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 1995 |
| 21074 | Owens, Don | | Oil Operator | Oct 2006 |
| 21075 | Owens, Rickey | Windsor, KY 42565 | Oil Operator | Dec 2022 |
| 21076 | Owi Operating Co. LC | Ottawa, KS 66067 | Oil & Gas Operator | Dec 2009 |
| 21077 | Owl Creek Operating Co., Inc. | Denver, CO 80206 | Oil & Gas Operator | Sep 2024 |
| 21078 | Owl Creek Production Co., Inc. | Houston, TX 77027 | Oil & Gas Operator | Apr 2006 |
| 21079 | Owl Creek Production Co., LLC | Denver, CO 80265 | Oil & Gas Operator | Jan 2006 |
| 21080 | Owl Operating Ventures L.L.C. | Midland, TX 79708 | Oil & Gas Operator | Dec 2022 |
| 21081 | Owl Ops II LLC | Midland, TX 79701 | Oil & Gas Operator | Sep 2024 |
| 21082 | Owl Ops LLC | Midland, TX 79701 | Oil & Gas Operator | Sep 2024 |
| 21083 | Own Resources Operating LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Jul 2024 |
| 21084 | Ows Acquisition Co LLC | Louisville, OH 44641 | Oil & Gas Operator | Dec 2023 |
| 21085 | Ows Energy LLC | Carlton, PA 16311-1605 | Oil & Gas Operator | Dec 2023 |
| 21086 | Ows Energy, Inc. | Montgomery, TX 77356 | Oil & Gas Operator | Sep 2024 |
| 21087 | Oxbow EP LLC | | Oil Operator | Dec 2023 |
| 21088 | Oxbow Oil Company,A Kansas General Partnership | Grenola, KS 67346 | Oil Operator | Apr 2015 |
| 21089 | Oxbow Petroleum, LLC | Midland, TX 79703 | Oil & Gas Operator | Sep 2024 |
| 21090 | Oxbow Properties Inc | Centennial, CO 80122-1422 | Oil & Gas Operator | Jul 2024 |
| 21091 | Oxco LLC | Pawhuska, OK 74056 | Oil & Gas Operator | Feb 2015 |
| 21092 | Oxenergy Incorporated | Flower Mound, TX 75022 | Oil & Gas Operator | Sep 2024 |
| 21093 | Oxford Explorati | | Oil & Gas Operator | Mar 1993 |
| 21094 | Oxford Exploration | | Oil Operator | Apr 1988 |
| 21095 | Oxford Exploration Company | Denver, CO 80237 | Oil & Gas Operator | Aug 1995 |
| 21096 | Oxford Oil | Zanesville, OH 43702-0910-0910 | Oil & Gas Operator | Dec 2012 |
| 21097 | Oxford Oil Co. | Rockdale, TX 76567 | Oil & Gas Operator | Aug 2004 |
| 21098 | Oxford Oil Inc | Cleveland, OK 74020 | Oil & Gas Operator | Feb 1997 |
| 21099 | Oxley Energy LLC | Houston, TX 77042 | Gas Operator | Jun 2024 |
| 21100 | Oxley John C | Tulsa, OK 74103 | Oil & Gas Operator | Sep 1996 |