| 21001 | Outlaw Oil LLC | Caldwell, TX 77836 | Oil & Gas Operator | Sep 2026 |
| 21002 | Outlaw Well Service LLC | Hays, KS 67601 | Oil Operator | May 2026 |
| 21003 | Outline Oil Company LLC | Beeville, TX 78104 | Oil Operator | Sep 2026 |
| 21004 | Outline Oil Corp. | San Antonio, TX 78217 | Oil & Gas Operator | Sep 2026 |
| 21005 | Outlook Petroleum Corp. | Midland, TX 79702 | Oil & Gas Operator | Jan 2001 |
| 21006 | Outman, Joshua J. | Andover, NY 14806 | Oil & Gas Operator | Dec 2025 |
| 21007 | Output Acquisition Corp. | | Oil & Gas Operator | Jul 2010 |
| 21008 | Output Exploration LLC | | Oil & Gas Operator | Dec 2006 |
| 21009 | Ouut Investing LLC | Mineral Wells, TX 76068 | Oil Operator | Mar 2020 |
| 21010 | Ovaco Energy Inc. | | Oil & Gas Operator | Nov 2009 |
| 21011 | Ovation Energy II, LP | Houston, TX 77279 | Oil & Gas Operator | Jun 2011 |
| 21012 | Ovation Energy, LP | N Richlnd HLS, TX 76180 | Oil & Gas Operator | Sep 2004 |
| 21013 | Overfield, Lee R | Waverly, KY 42462 | Oil Operator | Dec 2016 |
| 21014 | Overflow Energy Stack LLC | Booker, TX 79005 | Oil Operator | Sep 2022 |
| 21015 | Overflow Energy, LLC | Perryton, TX 79070 | Oil & Gas Operator | Sep 2026 |
| 21016 | Overland Exploration Company | | Oil Operator | May 2026 |
| 21017 | Overland Investments Inc | Coweta, OK 74429 | Oil & Gas Operator | Jun 2026 |
| 21018 | Overland Operating Company, LLC | Abilene, TX 79601 | Oil Operator | Sep 2026 |
| 21019 | Overland Resources LLC | Greenwood VIllage, CO 80111 | Oil & Gas Operator | Feb 2019 |
| 21020 | Overly Operating Co. | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2013 |
| 21021 | Overstreet, Jamie L | Hondo, TX 78861 | Oil & Gas Operator | Sep 2026 |
| 21022 | Overton Park Oil & Gas LP | Fort Worth, TX 76113 | Oil & Gas Operator | Sep 2026 |
| 21023 | Ovintiv Mid-Continent Inc. | The Woodlands, TX 77380-2764 | Oil & Gas Operator | Jul 2026 |
| 21024 | Ovintiv USA Inc. | Denver, CO 80202 | Oil & Gas Operator | Sep 2026 |
| 21025 | Owco Production Co., Inc. | | Oil Operator | Aug 1997 |
| 21026 | Owen Production Co | | Oil Operator | May 2001 |
| 21027 | Owen'S Pumping Service | | Oil Operator | May 2026 |
| 21028 | Owen, Matthew | Hamilton, KS 66853 | Oil Operator | Sep 2016 |
| 21029 | Owens James W | Tulsa, OK 74114-1425 | Oil & Gas Operator | Oct 2022 |
| 21030 | Owens Oil | | Oil Operator | Dec 2000 |
| 21031 | Owens Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Sep 2008 |
| 21032 | Owens Oil Company, LLC | Yates Center, KS 66783 | Oil Operator | May 2026 |
| 21033 | Owens Pet Inc | Midland, TX 79702 | Oil & Gas Operator | Aug 1995 |
| 21034 | Owens Petroleum | | Oil Operator | May 2006 |
| 21035 | Owens Petroleum LLC | Yates Center, KS 66783 | Oil & Gas Operator | May 2026 |
| 21036 | Owens Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 1995 |
| 21037 | Owi Operating Co. LC | Ottawa, KS 66067 | Oil & Gas Operator | Dec 2009 |
| 21038 | Owl Creek Operating Co., Inc. | Denver, CO 80206 | Oil & Gas Operator | Sep 2026 |
| 21039 | Owl Creek Production Co., Inc. | Houston, TX 77027 | Oil & Gas Operator | Apr 2006 |
| 21040 | Owl Creek Production Co., LLC | Denver, CO 80265 | Oil & Gas Operator | Jan 2006 |
| 21041 | Owl Operating Ventures L.L.C. | Midland, TX 79708 | Oil & Gas Operator | Dec 2022 |
| 21042 | Owl Ops II LLC | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 21043 | Owl Ops LLC | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 21044 | Own Resources Operating LLC | The Woodlands, TX 77381 | Oil & Gas Operator | May 2026 |
| 21045 | Ows Acquisition Co LLC | Louisville, OH 44641 | Oil & Gas Operator | Dec 2025 |
| 21046 | Ows Energy LLC | Carlton, PA 16311-1605 | Oil & Gas Operator | Jun 2026 |
| 21047 | Ows Energy, Inc. | Montgomery, TX 77356 | Oil & Gas Operator | Sep 2026 |
| 21048 | Oxbow EP LLC | Mathis, TX 78368 | Oil Operator | Sep 2026 |
| 21049 | Oxbow Oil Company,A Kansas General Partnership | Grenola, KS 67346 | Oil Operator | Apr 2015 |
| 21050 | Oxbow Petroleum, LLC | Midland, TX 79703 | Oil & Gas Operator | May 2025 |
| 21051 | Oxbow Properties Inc | Centennial, CO 80122-1422 | Oil & Gas Operator | Jan 2025 |
| 21052 | Oxco, LLC | | Oil & Gas Operator | Feb 2015 |
| 21053 | Oxenergy Incorporated | Flower Mound, TX 75022 | Oil & Gas Operator | Sep 2026 |
| 21054 | Oxford Explorati | | Oil & Gas Operator | Mar 1993 |
| 21055 | Oxford Exploration | | Oil Operator | Apr 1988 |
| 21056 | Oxford Exploration Company | Denver, CO 80237 | Oil & Gas Operator | Aug 1995 |
| 21057 | Oxford Oil | Zanesville, OH 43702 | Oil & Gas Operator | Dec 2012 |
| 21058 | Oxford Oil Co. | Rockdale, TX 76567 | Oil & Gas Operator | Aug 2004 |
| 21059 | Oxford Oil Inc | Cleveland, OK 74020 | Oil & Gas Operator | Feb 1997 |
| 21060 | Oxley Energy LLC | Houston, TX 77042 | Gas Operator | Jun 2026 |
| 21061 | Oxley John C | Tulsa, OK 74103 | Oil & Gas Operator | Sep 1996 |
| 21062 | Oxley Petroleum | Tulsa, OK 74119-3609 | Oil & Gas Operator | Jan 2020 |
| 21063 | Oxley Petroleum Company | Oklahoma City, OK 73118-1044 | Oil & Gas Operator | Sep 2017 |
| 21064 | Oxson Co. | Uvalde, TX 78802 | Gas Operator | Sep 2026 |
| 21065 | Oxtex Inc | | Oil & Gas Operator | Oct 1989 |
| 21066 | Oxxn | Weatherford, TX 76086 | Oil & Gas Operator | Oct 2023 |
| 21067 | Oxy Little Knife, LLC | | Oil & Gas Operator | Jan 2016 |
| 21068 | Oxy Petroleum Inc | | Oil & Gas Operator | Jan 1986 |
| 21069 | Oxy USA | | Oil Operator | Apr 1992 |
| 21070 | Oxy USA Eor, LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2026 |
| 21071 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Sep 2026 |
| 21072 | Oxy USA WTP Eor, LLC | Houston, TX 77002 | Oil Operator | Sep 2026 |
| 21073 | Oxy USA WTP Limited Partnership | Houston, TX 772104294 | Oil & Gas Operator | Jun 2026 |
| 21074 | Oxy USA WTP LP | Houston, TX 77046 | Oil & Gas Operator | Sep 2026 |
| 21075 | Oxyrock Operating, LLC | Houston, TX 77046 | Oil & Gas Operator | Sep 2026 |
| 21076 | Oz Gas Corporation | Tomball, TX 77377 | Gas Operator | Sep 2026 |
| 21077 | Oz Gas LTD | Tidioute, PA 16351-2648 | Oil & Gas Operator | Dec 2016 |
| 21078 | Ozark Enterprise | | Oil Operator | Nov 1990 |
| 21079 | Ozark Exploration, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Sep 2026 |
| 21080 | Ozark Oil Corporation | Springfield, MO 65804 | Oil & Gas Operator | Oct 1992 |
| 21081 | Ozark Oil LLC | Beallsville, OH 43716 | Oil & Gas Operator | Dec 2025 |
| 21082 | Ozark Production Company, Inc. | | Oil & Gas Operator | Jan 2025 |
| 21083 | Oztx Oil & Gas, L.L.C. | Ozona, TX 76943 | Oil & Gas Operator | Sep 2026 |
| 21084 | Ozzo Corporation, The | Bedford, TX 76021 | Oil Operator | Sep 2026 |
| 21085 | P & A Oilfield Services, Inc. | | Oil & Gas Operator | Jan 1998 |
| 21086 | P & A Operating, Inc. | Kerrville, TX 78028 | Oil & Gas Operator | Sep 2026 |
| 21087 | P & A Well Service | | Oil & Gas Operator | Jan 1994 |
| 21088 | P & C Energy Co | | Oil Operator | Dec 2015 |
| 21089 | P & C Oil & Gas, Inc. | Linn, WV 26384 | Oil & Gas Operator | Dec 2021 |
| 21090 | P & C Oil Company | Leona, TX 75850 | Oil & Gas Operator | Jul 2026 |
| 21091 | P & C Petroleum, LLC | Shawnee, KS 66226 | Oil Operator | Feb 2026 |
| 21092 | P & D Valentine Oil Co | New Matamoras, OH 45767 | Oil & Gas Operator | Dec 2018 |
| 21093 | P & E Oil | | Oil & Gas Operator | Dec 2025 |
| 21094 | P & F Operating, LLC | Dallas, TX 75206 | Oil & Gas Operator | Sep 2026 |
| 21095 | P & H Construction Inc | Wewoka, OK 74884 | Oil & Gas Operator | Mar 2026 |
| 21096 | P & H Oil & Gas Inc | Stroud, OK 74079 | Oil & Gas Operator | Jul 2026 |
| 21097 | P & H Vacuum Service | | Oil & Gas Operator | Jan 2025 |
| 21098 | P & J Resources, Inc | | Oil & Gas Operator | Dec 2013 |
| 21099 | P & M Construction | Graham, TX 76450 | Oil & Gas Operator | Sep 2026 |
| 21100 | P & M Drilling Company Inc | Depew, OK 74028 | Oil & Gas Operator | Dec 2004 |