| 1 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 2 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 3 | H2ok LLC | Marble Falls, TX 78654 | Oil & Gas Operator | Apr 2025 |
| 4 | Hadson Petro USA Inc | | Oil & Gas Operator | Nov 2016 |
| 5 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Nov 2018 |
| 6 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 7 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2025 |
| 8 | Hamil Oil & Gas LLC | Kingfisher, OK 73750-6500 | Oil & Gas Operator | Apr 2025 |
| 9 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Apr 2025 |
| 10 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 11 | Harrell Verlan W | Oklahoma City, OK 73102-7201 | Oil & Gas Operator | Nov 1999 |
| 12 | Hazelwood Louis J | Albuquerque, NM 87111-6870 | Oil & Gas Operator | Feb 2023 |
| 13 | Hazlewood Oil & Gas Co Inc | Oklahoma City, OK 73139-9353 | Oil & Gas Operator | Apr 2022 |
| 14 | HCM | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 15 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 16 | Helena Resources LLC | Helena, OK 73741 | Oil & Gas Operator | Apr 2025 |
| 17 | Hellard Elmer J | Sapulpa, OK 74066 | Oil & Gas Operator | May 2025 |
| 18 | Hennessey Oil & Gas LLC | Hennessey, OK 73742-0212 | Oil & Gas Operator | Sep 2024 |
| 19 | Henry Gungoll Operating Inc | Enid, OK 73703 | Oil & Gas Operator | May 2025 |
| 20 | Hep Oil Company LTD | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2012 |
| 21 | Hep Oil GP, LLC | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 22 | Highland Minerals, Inc. | Tulsa, OK 74145-7627 | Oil & Gas Operator | Apr 2015 |
| 23 | Highmark Energy Operating, LLC | Dallas, TX 75222 | Oil & Gas Operator | Jul 2025 |
| 24 | Hills Dozer Service | Stroud, OK 74079 | Oil & Gas Operator | Mar 2022 |
| 25 | HK Energy Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2023 |
| 26 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | May 2025 |
| 27 | Holke Dave Consulting Inc | Meridian, ID 83646-4812 | Oil & Gas Operator | Apr 2025 |
| 28 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Jul 2025 |
| 29 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 30 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 31 | HPC Incorporated | Denver, CO 80202 | Oil & Gas Operator | Nov 1998 |
| 32 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Jul 2025 |
| 33 | Hughes Gas Systems LLC | Dallas, TX 75214 | Oil & Gas Operator | Apr 2025 |
| 34 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 35 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Jul 2025 |
| 36 | Husky Ventures Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2025 |
| 37 | Hux Oil Company LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Apr 2025 |