| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | Hanson Natural Resources Co. | Oil & Gas Operator | Nov 1991 | |
| 2 | Harter Oil Company | Oil & Gas Operator | Apr 2011 | |
| 3 | Hawkeye Drilling Co. | Waskom, TX 75692 | Oil & Gas Operator | Feb 2023 |
| 4 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Oct 2025 |
| 5 | Hogan Drilling Company, Inc. | Oil & Gas Operator | Mar 1981 | |
| 6 | Hogan Exploration, Inc. | Oil & Gas Operator | Mar 2000 |