| 1 | H.E.R. Operating, LLC | Silsbee, TX 77656 | Oil & Gas Operator | Apr 2024 |
| 2 | H.K.E. | Stafford, TX 77497 | Oil & Gas Operator | Apr 2024 |
| 3 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Apr 2024 |
| 4 | Hanson Minerals Co. | Houston, TX 77042 | Oil & Gas Operator | Oct 1993 |
| 5 | Hanson Production Company | Cuero, TX 77954 | Oil & Gas Operator | Jul 2009 |
| 6 | Harvest Petroleum Inc. | Frisco, TX 75033 | Oil & Gas Operator | Apr 2024 |
| 7 | Heartland Resources, Inc. | Temple, TX 76501 | Oil & Gas Operator | Mar 2008 |
| 8 | Hennig Production Co., Inc. | Tyler, TX 75701 | Oil & Gas Operator | Apr 2024 |
| 9 | Heritage Operating Co., Inc. The | Stafford, TX 77497 | Oil & Gas Operator | May 1997 |
| 10 | High Plains Gas Systems, Inc. | Houston, TX 77019 | Oil & Gas Operator | Apr 2024 |
| 11 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Apr 2024 |
| 12 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Apr 2024 |
| 13 | Hopkins, T. M. Operating Co. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 14 | Hosford Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 1994 |
| 15 | Houston Oil & Minerals Corp. | Houston, TX 77002 | Oil & Gas Operator | Aug 1996 |
| 16 | Houston Petroleum Company | Houston, TX 77027 | Oil & Gas Operator | Apr 2024 |
| 17 | Howard Exploration, Inc. | Houston, TX 77069 | Oil & Gas Operator | Apr 2024 |
| 18 | HS Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 19 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Apr 2024 |
| 20 | Hughes, Dan A. Company | Beeville, TX 78104 | Oil & Gas Operator | May 2006 |
| 21 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 22 | Hunt Petroleum Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |