| 701 | American Delta Corporation | | Gas Operator | Jun 2013 |
| 702 | American Eagle Energy Corporation | | Oil & Gas Operator | Oct 2015 |
| 703 | American Eagle Oil | | Oil & Gas Operator | Dec 2010 |
| 704 | American Eagle Operating LLC | Gainesville, TX 76240 | Oil Operator | Jan 2019 |
| 705 | American Eagle Operating, Inc. | | Oil Operator | Aug 2010 |
| 706 | American Eagle Resources, Inc. | San Antonio, TX 78217-4802 | Oil & Gas Operator | Jan 2019 |
| 707 | American Energie | | Oil & Gas Operator | May 1995 |
| 708 | American Energies Pipeline, LLC | Dallas, TX 75206 | Oil & Gas Operator | Jan 2015 |
| 709 | American Energy | | Oil & Gas Operator | Jul 2004 |
| 710 | American Energy Associates Inc | Cortland, OH 44410 | Oil & Gas Operator | Dec 2017 |
| 711 | American Energy Corporation | Bealsville, OH 43716 | Oil & Gas Operator | Dec 2017 |
| 712 | American Energy Holdings, LLC | Weston, WV 26452 | Oil & Gas Operator | Dec 2017 |
| 713 | American Energy LLC | Lake Zurich, IL 60047-0129 | Oil & Gas Operator | Jul 2015 |
| 714 | American Energy Op. Corp.,The | | Oil & Gas Operator | Jan 2019 |
| 715 | American Energy Partners Inc | Boerne, TX 78006 | Oil & Gas Operator | Dec 2011 |
| 716 | American Energy Recovery Inc | Oklahoma City, OK 73123-0549 | Oil & Gas Operator | Nov 2015 |
| 717 | American Energy Resources, LLC | Phoenix, AZ 85013 | Oil Operator | Jun 2018 |
| 718 | American Energy Sources, Inc. | Spring, TX 77388 | Oil & Gas Operator | Dec 2008 |
| 719 | American Energy Utica LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Sep 2015 |
| 720 | American Energy-Perm Basin, LLC | Oklahoma City, OK 73113 | Oil & Gas Operator | May 2016 |
| 721 | American Explora | | Gas Operator | Apr 1994 |
| 722 | American Exploration | Houston, TX 77010 | Gas Operator | Apr 1994 |
| 723 | American Exploration Company | Houston, TX 77010-3088 | Oil & Gas Operator | Jan 2000 |
| 724 | American Exploration Oper. Co. | | Oil & Gas Operator | May 1990 |
| 725 | American Explorer, Inc. | | Oil & Gas Operator | Nov 2005 |
| 726 | American Hunter Explor LTD | Calgary Alberta Canada, T2P3H5 | Oil & Gas Operator | Dec 1993 |
| 727 | American Inland Resources Company LLC | Midland, TX 79705 | Oil & Gas Operator | Apr 2005 |
| 728 | American Int'L Energy Corp. | Houston, TX 77057 | Oil & Gas Operator | Nov 2015 |
| 729 | American Intl Production Inc. | | Oil & Gas Operator | Mar 1993 |
| 730 | American Land And Energy LLC | Castle Pines, CO 80108 | Oil Operator | Sep 2018 |
| 731 | American Lariat | | Oil Operator | Jun 1994 |
| 732 | American Midwest Oil & Gas Corp. | Billings, MT 59101 | Gas Operator | Nov 2018 |
| 733 | American National Petroleum Co. | Houston, TX 772277725 | Oil & Gas Operator | Aug 1995 |
| 734 | American Natural Energy Corp | Oklahoma City, OK 73114 | Oil & Gas Operator | Oct 2018 |
| 735 | American Natural Gas Inc | Saint Clairsville, OH 43950 | Oil & Gas Operator | Dec 2017 |
| 736 | American Natural Resources LLC | Tulsa, OK 74145-1117 | Oil & Gas Operator | Jun 2017 |
| 737 | American Nitrogen Rejection LLC | St Paul, MN 55113 | Gas Operator | May 2015 |
| 738 | American Oil & Gas, Inc. | | Oil & Gas Operator | Nov 2010 |
| 739 | American Oil LLC | Hays, KS 67601 | Oil Operator | Sep 2018 |
| 740 | American Oilfield Systems, Inc. | Oklahoma City, OK 73116 | Oil & Gas Operator | Jun 2001 |
| 741 | American Operating Company | | Gas Operator | Oct 2003 |
| 742 | American Operating Company (A) | Dallas, TX 75244 | Oil Operator | Jan 2019 |
| 743 | American Patriot Operating Corp. | Highland, IL 62249 | Oil Operator | Jan 2019 |
| 744 | American Petroel Inc A Corp | | Oil & Gas Operator | Dec 2017 |
| 745 | American Petrofina Co Of Texas | | Oil & Gas Operator | Jun 1985 |
| 746 | American Petrole | | Oil & Gas Operator | Dec 1996 |
| 747 | American Petroleum & Environmental Consultants Inc | Edmond, OK 73013-8801 | Oil Operator | May 2018 |
| 748 | American Petroleum & Mineral Co Inc | Seminole, OK 74818-1559 | Oil & Gas Operator | Nov 2018 |
| 749 | American Petroleum Corp. | Medusa, NY 12120 | Oil & Gas Operator | Jan 2019 |
| 750 | American Petroleum Energy Co | | Gas Operator | Nov 2018 |
| 751 | American Petroleum Exploration Corp. | Wichita, KS 67201 | Gas Operator | Feb 2002 |
| 752 | American Pumping & Trucking | New Braunfels, TX 78131-2580 | Oil & Gas Operator | Jan 2019 |
| 753 | American Quasar Petroleum | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 1985 |
| 754 | American Quasar Petroleum Co. | Jackson, MS | Oil & Gas Operator | Jun 1987 |
| 755 | American Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Jan 2019 |
| 756 | American Royalty | | Oil & Gas Operator | Oct 2005 |
| 757 | American Shoreline, Inc. | Corpus Chrsti, TX 78401-19 | Oil & Gas Operator | Jan 2019 |
| 758 | American Southwest Corp. | Jackson, MS | Oil & Gas Operator | Nov 1989 |
| 759 | American Star Energy & Min. Corp | Amarillo, TX 79102 | Oil & Gas Operator | Jan 2019 |
| 760 | American Tank Service LLC | Hays, KS 67601 | Oil Operator | Aug 2018 |
| 761 | American Trad.&Prod. | | Oil Operator | Dec 1995 |
| 762 | American Trading | | Oil & Gas Operator | Dec 1995 |
| 763 | American Trading & Prod Corp | Houston, TX 77040-6471 | Oil & Gas Operator | Nov 2014 |
| 764 | American Trading Et Al | | Oil & Gas Operator | Apr 1979 |
| 765 | American Warrior | | Oil & Gas Operator | Sep 2018 |
| 766 | American Warrior Inc | Garden City, KS 67846 | Oil & Gas Operator | Sep 2018 |
| 767 | American Warrior, In | | Oil & Gas Operator | Sep 2018 |
| 768 | American West | Burkett, TX 76828-301 | Oil & Gas Operator | Jan 2019 |
| 769 | American West Resources, Inc | | Oil & Gas Operator | Jan 2019 |
| 770 | Americana Energy Inc | Byng, OK 74820-9574 | Oil & Gas Operator | Oct 2018 |
| 771 | Americase Production Co. | Dallas, TX 75252 | Oil Operator | May 2002 |
| 772 | Americo Energy Resources, LLC | Houston, TX 77063 | Oil & Gas Operator | Jan 2019 |
| 773 | Americo Oil Company | Oklahoma City, OK 73154-0964 | Oil & Gas Operator | Mar 2015 |
| 774 | Amerikan Oil, LLC | Mound City, KS 66056 | Oil Operator | Sep 2018 |
| 775 | Amerind Oil Co L P | Midland, TX 79701 | Oil & Gas Operator | Nov 2004 |
| 776 | Amerind Oil Company, LTD. | Midland, TX 79701 | Oil & Gas Operator | Nov 2004 |
| 777 | Ameristate Exploration LLC | Austin, TX 78701 | Oil & Gas Operator | Nov 2009 |
| 778 | Ameritech Oil & Gas Corporation | | Oil & Gas Operator | May 1996 |
| 779 | Amerkan Resource | | Oil Operator | Jan 1994 |
| 780 | Amerril Energy LLC | Houston, TX 77042 | Oil & Gas Operator | Jan 2019 |
| 781 | Ames Financial, Inc | Shreveport, LA 71101 | Oil & Gas Operator | May 2018 |
| 782 | Ames Oil | Cross Plains, TX 76443 | Oil & Gas Operator | Jan 2019 |
| 783 | Ames Oil Corporation Of Texas | | Oil & Gas Operator | Mar 2008 |
| 784 | Amex Energy Consults Inc | Columbus, OH 43214 | Oil & Gas Operator | Dec 1988 |
| 785 | Amexco, LLC | San Antonio, TX 78259 | Oil & Gas Operator | Jan 2019 |
| 786 | Amherst Energy Holdings, LLC | Flower Mound, TX 75022 | Oil Operator | Jan 2019 |
| 787 | Aminex USA, Inc. | Somerset, TX 78069 | Oil & Gas Operator | May 2018 |
| 788 | Aminoil USA, Inc. | | Oil & Gas Operator | Dec 1984 |
| 789 | Amirmex Inc. | Denver, CO 80234-1770 | Oil & Gas Operator | Jan 2019 |
| 790 | Amistad Energy Services, LLC | Katy, TX 77450 | Oil & Gas Operator | Oct 2017 |
| 791 | Amity Oil Co., Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 1977 |
| 792 | Amkay Petroleum Co., Inc. | | Oil Operator | Dec 1991 |
| 793 | Ammo Energy, LLC | | Oil & Gas Operator | Feb 2009 |
| 794 | Ammonite Energy Texas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Aug 2003 |
| 795 | Amoco Production | | Oil & Gas Operator | Jun 2012 |
| 796 | Amoco Production Co And C M S Oil And Gas | | Oil & Gas Operator | Sep 1996 |
| 797 | Amoco Production Co-Ratliff City | | Oil Operator | May 1998 |
| 798 | Amoco Production Co. | Tulsa, OK 74102-0591 | Oil & Gas Operator | Jun 2015 |
| 799 | Amoco Rocmount Company | Denver, CO 80201 | Oil & Gas Operator | Jan 1998 |
| 800 | Amos Zittel & Sons, Inc. | Eden, NY 14057 | Gas Operator | Dec 2017 |