| 701 | Hazen Oil Company | Cleveland, OK 74020-9633 | Oil Operator | Jul 2020 |
| 702 | Hazen, Paul D. | Great Bend, KS 67530 | Oil Operator | Nov 1990 |
| 703 | Hazen, Ty Anthony | Lyons, KS 67554 | Oil Operator | Sep 2025 |
| 704 | Hazlewood Oil & Gas Co Inc | Oklahoma City, OK 73139-9353 | Oil & Gas Operator | Apr 2022 |
| 705 | Hazlewood-Patterson Company | Keller, TX 76244 | Gas Operator | Jun 2006 |
| 706 | Hazoco, L.L.C. | Bellville, TX 77418 | Oil Operator | Feb 2026 |
| 707 | HB Energy LLC | Wellsville, KS 66092 | Oil Operator | Sep 2025 |
| 708 | HB Oil Company | Abilene, TX 79602 | Oil & Gas Operator | Jun 2023 |
| 709 | HBC Oil Company, LLC | San Antonio, TX 78266 | Oil Operator | Feb 2026 |
| 710 | HC Resources, Inc. | | Oil & Gas Operator | Jul 2011 |
| 711 | Hce Operating LLC | Smyer, TX 79367 | Oil & Gas Operator | Feb 2026 |
| 712 | HCG Energy Corporation & Subs | | Oil & Gas Operator | Mar 2015 |
| 713 | HCL Inc | Woodward, OK 73802-1074 | Oil Operator | Mar 2015 |
| 714 | HCM | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 715 | HCM Resources LLC | Guymon, OK 73942 | Gas Operator | Mar 2015 |
| 716 | HCW Exploration, Inc. | | Oil & Gas Operator | Jun 1986 |
| 717 | HD Special-Situations, LP | San Francisco, CA 94111 | Oil & Gas Operator | Feb 2014 |
| 718 | HD Well Services LLC | Wellsville, KS 66092 | Oil Operator | Sep 2025 |
| 719 | HDH Resources, Inc. | Wilmore, KS 67155 | Oil & Gas Operator | Jul 2025 |
| 720 | HDS Production | | Oil Operator | Mar 1998 |
| 721 | HDT Inc. | | Oil & Gas Operator | Dec 2025 |
| 722 | Headington Canada Corp. | Dallas, TX 75231 | Gas Operator | Jun 2000 |
| 723 | Headington Energy Corporation | | Oil & Gas Operator | Aug 1992 |
| 724 | Headington Energy Partners, LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Feb 2026 |
| 725 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 726 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 727 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 728 | Headline Resources, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Aug 1997 |
| 729 | Headwaters Energy Partners, LLC | Dripping SPGS, TX 78620 | Oil & Gas Operator | Feb 2026 |
| 730 | Headwaters Oil Company | | Oil & Gas Operator | Oct 1981 |
| 731 | Heady, Harold | Parsons, KS 67357 | Gas Operator | Aug 2016 |
| 732 | Heape Exploration, Inc. | Dallas, TX 75367 | Oil & Gas Operator | Dec 2020 |
| 733 | Heape, Gene G. | Dallas, TX 75367 | Oil & Gas Operator | Jun 2003 |
| 734 | Hearn Oil Co. LLC | Newport, OH 45768 | Oil & Gas Operator | Dec 2024 |
| 735 | Heart Land Petroleum Corporation | Abilene, TX 79604 | Oil & Gas Operator | Mar 2008 |
| 736 | Heartland Energy Company | Big Horn, WY 82833 | Gas Operator | Jun 2012 |
| 737 | Heartland Energy Corp | Rockville, MD 208531658 | Gas Operator | Jun 1997 |
| 738 | Heartland Enterprises, Incorporated | Phillipsburg, KS 67661 | Oil Operator | May 2005 |
| 739 | Heartland Environmental Services | Watonga, OK 73080 | Oil & Gas Operator | May 1999 |
| 740 | Heartland Exploration | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2000 |
| 741 | Heartland Exploration Inc | Edmond, OK 73013 | Oil & Gas Operator | Dec 2015 |
| 742 | Heartland Oil & Gas Inc. | Gypsum, KS 67448 | Gas Operator | Jun 2011 |
| 743 | Heartland Production, Inc. | Cuero, TX 77954 | Oil & Gas Operator | Feb 2026 |
| 744 | Heartland Pumping | Hennessey, OK 73742-7311 | Oil & Gas Operator | Nov 2025 |
| 745 | Heartland Resources, Inc. | Temple, TX 76501 | Oil & Gas Operator | Mar 2008 |
| 746 | Heartlands Development Co Inc | Bristow, OK 74010-3826 | Oil & Gas Operator | May 2017 |
| 747 | Heat Can Oil, LLC | Chanute, KS 66720 | Oil Operator | Jun 2009 |
| 748 | Heat Controller Inc | Jackson, MI 49204 | Oil & Gas Operator | Dec 1996 |
| 749 | Heat Waves Hot Oil Service LLC | Denver, CO 80202 | Oil Operator | Jun 2011 |
| 750 | Heath 91 Cluster LP | Commodore, PA 15729-9109 | Gas Operator | Dec 2025 |
| 751 | Heath Jack A | Tulsa, OK 74132-2403 | Oil & Gas Operator | Jan 2013 |
| 752 | Heath Oil Co., Inc. | Washington, OK 73093-4702 | Oil & Gas Operator | Nov 2025 |
| 753 | Heath, Chad | Greensburg, KY 42743 | Oil Operator | Dec 2023 |
| 754 | Heath, Francis A. & Ruth E. | South Dayton, NY 14138 | Gas Operator | Dec 2024 |
| 755 | Heath, Mark | Leoti, KS 67861 | Oil Operator | Nov 2009 |
| 756 | Heather & Randy Iantorno Oil | Bolivar, NY 14715 | Oil & Gas Operator | Dec 2024 |
| 757 | Heatherly, Darl H. | Belington, WV 26250 | Gas Operator | Dec 2021 |
| 758 | Heaton Everill L | Exeter, CA 93221-2340 | Oil & Gas Operator | Sep 2014 |
| 759 | Hebert & Rucks L.L.C. | | Oil & Gas Operator | May 2002 |
| 760 | Hebron Energy, LLC | Dallas, TX 75206 | Oil Operator | Jul 2018 |
| 761 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 762 | Hedges Spencer | Casper, WY 82604 | Oil Operator | Mar 2024 |
| 763 | Hedrick Production Inc. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Feb 2026 |
| 764 | Hedrick, Thomasine | Severy, KS 67137 | Oil Operator | May 2011 |
| 765 | Heflin, Bryan Exploration, Inc. | Strawn, TX 76475 | Oil & Gas Operator | Mar 2008 |
| 766 | Heger J J & Asso | | Oil Operator | Jun 1983 |
| 767 | Hegwald, Jacob L. | Humboldt, KS 66748 | Oil Operator | Nov 2019 |
| 768 | Hehns Quality Gardens Inc | Wadsworth, OH 44281 | Oil & Gas Operator | Dec 2024 |
| 769 | Heifer Production Company LLC | Houston, TX 77098 | Oil & Gas Operator | Feb 2026 |
| 770 | Heights Energy Corporation | Plano, TX 75026 | Oil & Gas Operator | Feb 2026 |
| 771 | Heim, William J. | Springville, NY 14141 | Gas Operator | Dec 2024 |
| 772 | Heineman, Ronald F. | Caledonia, NY 14423 | Gas Operator | Dec 2024 |
| 773 | Heinrich Enterprises Inc Dba Washington Operations | Reno, OH 45773 | Oil & Gas Operator | Dec 2024 |
| 774 | Heinrich Enterprises, Inc. | Reno, OH 45773-0305 | Oil & Gas Operator | Dec 2021 |
| 775 | Heinrich Production Co Inc | Lubbuck, TX 79424 | Oil Operator | Dec 2024 |
| 776 | Heintz Gas & Oil Company, Inc. | Allegany, NY 14706 | Gas Operator | Dec 2024 |
| 777 | Heisey Ventures, Inc. | Houston, TX 77019 | Oil & Gas Operator | Feb 2026 |
| 778 | Helberg Oil Comp | | Oil Operator | Mar 1995 |
| 779 | Helbing & Podpechan | Clarence, OK 74018 | Oil & Gas Operator | May 1983 |
| 780 | Helbing & Robert | | Oil & Gas Operator | Feb 1991 |
| 781 | Held By Producti | | Oil & Gas Operator | Feb 1995 |
| 782 | Held By Production, Inc. | Houston, TX 77251 | Oil & Gas Operator | May 1996 |
| 783 | Helemrich & Payne Inc | Iraan, TX 79744 | Oil & Gas Operator | Sep 2002 |
| 784 | Helena Production Corp | | Oil & Gas Operator | Dec 1991 |
| 785 | Helena Resources Inc | Lakewood, CO 80215 | Oil & Gas Operator | Oct 2025 |
| 786 | Helena Resources LLC | Helena, OK 73741 | Oil & Gas Operator | Nov 2025 |
| 787 | Helios Operating, LLC | Houston, TX 77056 | Oil & Gas Operator | Feb 2026 |
| 788 | Helis Oil & Gas Company LLC Estate | New Orleans, LA 70130 | Oil & Gas Operator | Jul 2022 |
| 789 | Helis Oil & Gas Company, L.L.C. | New Orleans, LA 70130 | Oil & Gas Operator | Oct 2023 |
| 790 | Helis, William G. Co., LLC, The | New Orleans, LA 70130 | Oil & Gas Operator | Oct 2003 |
| 791 | Helis,WM.G.,Est., A Partnership | New Orleans, LA 70130 | Oil & Gas Operator | Aug 2003 |
| 792 | Helke Exploration Company | Oklahoma City, OK 73112-7201 | Oil & Gas Operator | Feb 2000 |
| 793 | Hellar Drilling | | Oil & Gas Operator | Jan 1994 |
| 794 | Hellar Drilling Company, Inc. | Wichita, KS 67208 | Oil & Gas Operator | Jan 2009 |
| 795 | Hellard Elmer J | Sapulpa, OK 74066 | Oil & Gas Operator | Dec 2025 |
| 796 | Heller Phillip & Charlene | Columbia, MO 65201 | Oil & Gas Operator | Nov 2025 |
| 797 | Hellifino Operating, LLC | San Antonio, TX 78212 | Oil Operator | Feb 2026 |
| 798 | Hellman Properties LLC | | Oil & Gas Operator | Dec 2025 |
| 799 | Hellums, Harold | Cedar Creek, TX 78612 | Oil & Gas Operator | Mar 2008 |
| 800 | Helm Energy Company | Tulsa, OK 74133 | Oil Operator | Sep 2025 |