| 1 | H & S Drilling Co Inc | Frazeysburg, OH 43822-0040-0040 | Oil & Gas Operator | Dec 2016 |
| 2 | H & S Production, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Mar 2004 |
| 3 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Aug 2024 |
| 4 | Hansen Oil Corporation | Shreveport, LA 71106 | Oil Operator | Apr 2003 |
| 5 | Harleton Oil & Gas Inc. | Tyler, TX 75710 | Oil & Gas Operator | Mar 2025 |
| 6 | Harman Operating Company, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 2007 |
| 7 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 8 | Hemus, Inc. | Bellaire, TX 77401 | Oil & Gas Operator | Sep 1994 |
| 9 | Hibbard Energy, LP | Whitehouse, TX 75791 | Oil & Gas Operator | Mar 2025 |
| 10 | Hinton Production Company | MT Pleasant, TX 75455 | Oil & Gas Operator | Aug 1995 |
| 11 | Hootkins, Seymour G. | Archer City, TX 76351 | Oil & Gas Operator | Apr 1997 |
| 12 | Houston Exploration Co, The | Houston, TX 77002 | Oil & Gas Operator | Apr 2017 |
| 13 | Howell Oil & Gas, Inc. | Marshall, TX 75671 | Oil & Gas Operator | Oct 2019 |
| 14 | Hughey, W. R., Operating Co. | Tyler, TX 75711 | Oil & Gas Operator | Feb 2005 |
| 15 | Hugus Investment Company, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 16 | Humak Processors, Inc. | Tyler, TX 75710 | Oil & Gas Operator | Aug 2005 |
| 17 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Mar 2025 |
| 18 | Hunt Petroleum Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 19 | Hunt, WM. Herbert, Trust Est. | Dallas, TX 75201 | Oil & Gas Operator | Sep 1998 |