| 1 | H B Oil & Gas Inc | Oklahoma City, OK 73159 | Oil & Gas Operator | Jun 2000 |
| 2 | H.L.S. Energy Co., Inc. | Uvalde, TX 78801 | Oil & Gas Operator | Aug 2003 |
| 3 | Hadson Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 4 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Jun 2025 |
| 5 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 6 | Hamilton K M Oil & Gas Co | Ada, OK 74820 | Oil Operator | Jan 2013 |
| 7 | Hammer Oil Properties Inc | Enid, OK 73706-0144 | Oil & Gas Operator | Oct 2017 |
| 8 | Hanna Oil And Gas Company | Fort Smith, AR 72901 | Oil & Gas Operator | Jun 2025 |
| 9 | Harbor Resources LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Oct 2025 |
| 10 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Jun 2025 |
| 11 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 12 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 13 | Hazelwood Prod & Exp Co LLC | Oklahoma City, OK 73116-9037 | Oil & Gas Operator | Jun 2025 |
| 14 | Hazlewood Oil & Gas Co Inc | Oklahoma City, OK 73139-9353 | Oil & Gas Operator | Apr 2022 |
| 15 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 16 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 17 | Heartland Pumping | Hennessey, OK 73742-7311 | Oil & Gas Operator | Jul 2025 |
| 18 | Helke Exploration Company | Oklahoma City, OK 73112-7201 | Oil & Gas Operator | Feb 2000 |
| 19 | Hennessey Oil & Gas LLC | Hennessey, OK 73742-0212 | Oil & Gas Operator | Sep 2024 |
| 20 | Henry Gungoll Operating Inc | Enid, OK 73703 | Oil & Gas Operator | Jul 2025 |
| 21 | Henry Oil & Gas Inc | Oklahoma City, OK 73127 | Oil & Gas Operator | Jul 2009 |
| 22 | Heritage Exploration LLC | Oklahoma City, OK 73120-5622 | Oil & Gas Operator | Jan 2020 |
| 23 | Heritage Petroleum, Inc. | Stillwater, OK 74076 | Oil & Gas Operator | Oct 2025 |
| 24 | Heston Oil Company | Tulsa, OK 74108 | Oil & Gas Operator | Mar 2005 |
| 25 | Hewitt Energy Group, Inc. | Salt Lake City, UT 84111 | Oil & Gas Operator | Apr 2015 |
| 26 | HHL Development Inc | Garber, OK 73738 | Oil & Gas Operator | Jul 2025 |
| 27 | High Energy | Cushing, OK 74023 | Oil & Gas Operator | May 2025 |
| 28 | Himco Oil & Gas, Inc. | Enid, OK 73702 | Oil & Gas Operator | Jun 2025 |
| 29 | Hinkle Engineering, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2016 |
| 30 | Hinkle Oil And Gas Inc | Oklahoma City, OK 73112-4275 | Oil & Gas Operator | Jul 2025 |
| 31 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | Jul 2025 |
| 32 | Hodge T F | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2007 |
| 33 | Hoehn French | Enid, OK 73701-5600 | Oil & Gas Operator | Oct 1996 |
| 34 | Holden Energy Corporation | Ardmore, OK 73401 | Oil & Gas Operator | Mar 2015 |
| 35 | Hondo Oil & Gas Company | Roswell, NM 88202 | Oil & Gas Operator | Aug 2006 |
| 36 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 37 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 38 | Hovas Enterprises | Perkins, OK 74059 | Oil & Gas Operator | Mar 2014 |
| 39 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Oct 2025 |
| 40 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 41 | Huitt Joe A | Tulsa, OK 74103 | Oil & Gas Operator | May 2001 |
| 42 | Huitt Joe A Rev Trust | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2009 |
| 43 | Hulen Operating Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 44 | Hulsey Larry O & Co | Graham, TX 76046 | Oil & Gas Operator | Jun 2012 |
| 45 | Hungerford Oil & Gas Inc | Helena, OK 73741 | Oil & Gas Operator | Nov 2000 |
| 46 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 47 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 48 | Hunton Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Jun 2025 |
| 49 | Husky Ventures Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Jun 2025 |
| 50 | Hux Oil Company LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Jul 2025 |
| 51 | Hyalite Energy Corporation | Pampa, TX 79066 | Oil & Gas Operator | May 2025 |