| 801 | Amtex Energy | | Oil & Gas Operator | Aug 1995 |
| 802 | Amtex Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2019 |
| 803 | Amtex Oil & Gas Inc | Canton, OH 44711 | Oil & Gas Operator | Dec 2004 |
| 804 | Amtuck Oil | Logan, OH 43138 | Oil & Gas Operator | Dec 2010 |
| 805 | Amvest Osage Inc | Skiatook, OK 74070-0970 | Oil & Gas Operator | Dec 2015 |
| 806 | Amwar Expl. & Allen Petroleum | Natchez, MS 39121 | Oil & Gas Operator | Apr 2019 |
| 807 | Amwes Exploration, LLC | Barbourville, KY 40906 | Oil & Gas Operator | Dec 2015 |
| 808 | Amx Energy, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jun 2019 |
| 809 | An-Car Oil Co Inc | Owensboro, KY 42302-1329 | Oil & Gas Operator | Dec 2014 |
| 810 | An-Son Corp | Oklahoma City, OK 73124-0060 | Gas Operator | Feb 2018 |
| 811 | Anacapa Oil Corporation | Sutter, CA 95982 | Gas Operator | Feb 2018 |
| 812 | Anadarko Austin Chalk Company | Houston, TX 77251 | Oil & Gas Operator | Feb 2006 |
| 813 | Anadarko E&P Company LP | Houston, TX 77251-1330 | Oil & Gas Operator | Oct 2014 |
| 814 | Anadarko E&P Onshore LLC | Houston, TX 77251-1330 | Oil & Gas Operator | Dec 2019 |
| 815 | Anadarko Gathering Co. | Houston, TX 77251 | Oil Operator | Jul 2001 |
| 816 | Anadarko Minerals, Inc. | Oklahoma City, OK 73102-8606 | Oil & Gas Operator | Apr 2019 |
| 817 | Anadarko Petrole | | Oil & Gas Operator | Dec 1996 |
| 818 | Anadarko Petroleum | | Oil & Gas Operator | Oct 2007 |
| 819 | Anadarko Petroleum Co | | Oil & Gas Operator | Feb 1998 |
| 820 | Anadarko Petroleum Corporation | Houston, TX 77251-1330 | Oil & Gas Operator | Feb 2019 |
| 821 | Anadarko Prod | | Oil & Gas Operator | Dec 1996 |
| 822 | Anadarko Production Co. | | Oil Operator | Feb 1989 |
| 823 | Anadarko Water Resource MGMT LLC | Burns Flat, OK 73624-0229 | Gas Operator | Dec 2018 |
| 824 | Anadime Energy Services Inc. | | Oil & Gas Operator | Dec 2009 |
| 825 | Ananda Energy Inc. | Pampa, TX 79065 | Oil & Gas Operator | Jun 2019 |
| 826 | Anaqua Oil & Gas, Inc. | | Oil & Gas Operator | Mar 2008 |
| 827 | Anatexas Offshore, Inc. | Houston, TX 77024-2763 | Gas Operator | Jun 2019 |
| 828 | Anathema, Inc. | | Oil & Gas Operator | Dec 1994 |
| 829 | Anc Investments LLC | Enid, OK 73701-1823 | Gas Operator | Jan 2015 |
| 830 | Ancell Oil Co. | Wichita Falls, TX 76309 | Oil & Gas Operator | Dec 2018 |
| 831 | Ancho Oil LLC | El Paso, TX 79912 | Oil Operator | Jun 2019 |
| 832 | Anchor B Production, Inc. | | Oil & Gas Operator | Aug 2003 |
| 833 | Anchor Bay Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2007 |
| 834 | Anchor Bay Petroleum | Hays, KS 67601 | Oil Operator | Feb 2019 |
| 835 | Anchor Bay Petroleum LLC | Hays, KS 67601 | Oil Operator | Feb 2019 |
| 836 | Anchor Oil Company | Spearman, TX 79081 | Gas Operator | Jun 2019 |
| 837 | Anchor Operating Co. | Houston, TX 77055 | Oil & Gas Operator | Jun 2019 |
| 838 | Anchor Petroleum, Inc. | | Oil & Gas Operator | Jan 1996 |
| 839 | Ancient Sands Inc | Kittanning, PA 16201-0916 | Oil & Gas Operator | Dec 2008 |
| 840 | Anco Account | | Oil & Gas Operator | Oct 1995 |
| 841 | Ancora-Verde Corporation | | Oil & Gas Operator | Dec 2004 |
| 842 | Ancro Oil & Gas Inc | | Oil & Gas Operator | Dec 2017 |
| 843 | Andalucia Oil Company | | Oil Operator | Jun 2019 |
| 844 | Andector Exploration Company | Midland, TX 79702 | Oil & Gas Operator | Jun 2019 |
| 845 | Anderman/Smith Operating Company | Shreveport, LA 71101 | Oil & Gas Operator | Jan 1999 |
| 846 | Anderson And Wells Oil Co | | Oil & Gas Operator | Dec 2006 |
| 847 | Anderson Art Tan | | Oil Operator | Jul 1988 |
| 848 | Anderson Bobby B | Fleming, OH 45729 | Oil & Gas Operator | Dec 2018 |
| 849 | Anderson Energy Corporation | Arvada, CO 80004 | Oil & Gas Operator | Jun 2019 |
| 850 | Anderson Energy Inc | Wichita, KS 67202 | Oil & Gas Operator | Feb 2019 |
| 851 | Anderson Floyd Melton Revocable Trust | Yukon, OK 73099-5656 | Oil Operator | Jul 2015 |
| 852 | Anderson Kent | | Oil Operator | Dec 2009 |
| 853 | Anderson Management Company | | Oil & Gas Operator | Dec 2014 |
| 854 | Anderson Oil & Gas Account | | Oil & Gas Operator | May 1999 |
| 855 | Anderson Oil Company | Washington, MS 39190 | Oil & Gas Operator | Oct 2015 |
| 856 | Anderson Oil Corporation | Corpus Chrsti, TX 78403-2524 | Oil & Gas Operator | Nov 1999 |
| 857 | Anderson Oil LTD. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jun 2019 |
| 858 | Anderson Oil LTD.,LLP | Farmington, NM 87499 | Oil & Gas Operator | Jan 2019 |
| 859 | Anderson Operating LLC Of Mississippi | | Oil & Gas Operator | Oct 2018 |
| 860 | Anderson Operating, LLC | Washington, MS 39190 | Oil & Gas Operator | Apr 2019 |
| 861 | Anderson Petro-Equipment, Inc. | Montgomery, TX 77356-8944 | Oil & Gas Operator | Jun 2019 |
| 862 | Anderson Producing, Inc. | | Oil & Gas Operator | Sep 2013 |
| 863 | Anderson Production | Cisco, TX 76437 | Oil & Gas Operator | Jun 2019 |
| 864 | Anderson Thornto | | Oil & Gas Operator | Mar 1995 |
| 865 | Anderson, Allen M | Fleming, OH 45729 | Oil & Gas Operator | Dec 2018 |
| 866 | Anderson, Arden A. | | Oil & Gas Operator | Jun 1970 |
| 867 | Anderson, Carl T. | | Oil & Gas Operator | Jan 1999 |
| 868 | Anderson, Dorman | | Oil & Gas Operator | Dec 2012 |
| 869 | Anderson, E D | | Oil & Gas Operator | Nov 2009 |
| 870 | Anderson, James K. Inc. | Norman, OK 73070-1188 | Oil & Gas Operator | Jun 2019 |
| 871 | Anderson, Jerry | Floydada, TX 79235 | Oil & Gas Operator | Feb 2019 |
| 872 | Anderson, Kendra A. | Galva, KS 67443 | Oil Operator | Feb 2019 |
| 873 | Anderson, Kyle K | Concord, NY 14055 | Gas Operator | Dec 2017 |
| 874 | Anderson, Roger W. Corp. | Clyde, TX 79510-835 | Oil & Gas Operator | Jun 2019 |
| 875 | Anderson, Steven C. | Victoria, TX 77902 | Gas Operator | Jun 2004 |
| 876 | Ando Energy, Inc. | | Oil & Gas Operator | Feb 1998 |
| 877 | Andover Oil Comp | | Oil & Gas Operator | Oct 1989 |
| 878 | Andover Oil Company | | Oil Operator | Sep 1982 |
| 879 | Andress Bill O | Tulsa, OK 74135-3553 | Gas Operator | Apr 1990 |
| 880 | Andrew Alan Exploration, Inc. | Longview, TX 75606 | Oil & Gas Operator | Mar 2017 |
| 881 | Andrew L. Newkirk | Taft, CA 93268 | Oil Operator | Mar 2016 |
| 882 | Andrew, Robert Oneal | | Oil & Gas Operator | Sep 1998 |
| 883 | Andrews & Corkran, L.L.C. | Austin, TX 78746 | Oil & Gas Operator | Feb 2000 |
| 884 | Andrews Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Jun 2019 |
| 885 | Andrews, B. C. | | Oil & Gas Operator | Jun 2019 |
| 886 | Andries Oil Company | | Oil Operator | Sep 2018 |
| 887 | Andrikopoulos Resources* A G | | Oil & Gas Operator | Jul 2015 |
| 888 | Andrus Resources Corporation | | Oil & Gas Operator | Oct 2002 |
| 889 | Anegada Resources | | Oil & Gas Operator | Jan 2002 |
| 890 | Angel Exploration Company | Oklahoma City, OK 73102-8868 | Oil & Gas Operator | Apr 2018 |
| 891 | Angel Exploration LLC | Oklahoma City, OK 73116-3603 | Oil & Gas Operator | Apr 2019 |
| 892 | Angel Rose Energy, LLC | | Oil Operator | Dec 2011 |
| 893 | Angelo, Ernest, Jr. | Midland, TX 79701 | Oil & Gas Operator | Mar 2008 |
| 894 | Angerman Assoc Inc | Pittsburgh, PA 15238-1359 | Oil & Gas Operator | Dec 1998 |
| 895 | Angerman Associates Inc | | Oil & Gas Operator | Mar 1998 |
| 896 | Angle Exploratio | | Oil Operator | Jan 1987 |
| 897 | Angle George A | | Gas Operator | Dec 1986 |
| 898 | Angle Oil Compan | | Oil Operator | Jun 1994 |
| 899 | Angle Oil Company | Hays, KS 67601 | Oil Operator | Sep 2002 |
| 900 | Anglo Production Company | | Oil & Gas Operator | Nov 1983 |