| 1 | H & L Exploration Company, LLC | Amarillo, TX 79114 | Oil & Gas Operator | Oct 2025 |
| 2 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 3 | H & L Operating Co., LLC | Amarillo, TX 79114 | Oil & Gas Operator | Mar 2021 |
| 4 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 5 | H-S Exploration | Perryton, TX 79070 | Oil & Gas Operator | Oct 2025 |
| 6 | H.D. Smith, Inc. | Waller, TX 77484 | Oil Operator | Oct 2025 |
| 7 | Hadaway Consult And Engineer,LLC | Canadian, TX 79014 | Oil & Gas Operator | Oct 2025 |
| 8 | Hadaway Engineering Inc | Canadian, TX 79014 | Oil & Gas Operator | Jul 2015 |
| 9 | Hadson Energy Resources Corp. | Houston, TX 77056 | Oil & Gas Operator | Dec 1994 |
| 10 | Haider Operating, LLC | Pampa, TX 79066 | Oil & Gas Operator | Oct 2025 |
| 11 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 12 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 13 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 14 | Harper Production, LLC | Spearman, TX 79081 | Oil & Gas Operator | Oct 2025 |
| 15 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 16 | Haywood, Paul M. Jr. | Denton, TX 76206 | Oil & Gas Operator | Mar 2002 |
| 17 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 18 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 19 | Headline Resources, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Aug 1997 |
| 20 | Hicks Exploration, LLC | Dover, OK 73734 | Gas Operator | Feb 2025 |
| 21 | Highmark Energy Operating, LLC | Dallas, TX 75222 | Oil & Gas Operator | Oct 2025 |
| 22 | Hodgden, Jack D. | Enid, OK 73702 | Oil & Gas Operator | Apr 2000 |
| 23 | Holmes Exploration, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2015 |
| 24 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 25 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 26 | Horizon Oil & Gas Co. | Dallas, TX 75221 | Oil & Gas Operator | Jan 2005 |
| 27 | HRB Operating Company, Inc. | Bridgeport, TX 76426 | Oil & Gas Operator | Oct 2025 |
| 28 | HS Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 29 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Oct 2025 |
| 30 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 31 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 32 | Hy-Tech, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Feb 2017 |
| 33 | Hyalite Energy Corporation | Pampa, TX 79066 | Oil & Gas Operator | May 2025 |