| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | H. O. Strickler Operator | Oil & Gas Operator | Dec 1993 | |
| 2 | H.T. Olsen Oil & Gas Operations | Oil & Gas Operator | Mar 2026 | |
| 3 | Hathaway Company | Oil & Gas Operator | Dec 2025 | |
| 4 | Hilliard Oil & Gas, Inc. | New Orleans, LA 70112 | Oil & Gas Operator | May 2001 |
| 5 | Holmes Western Oil Corporation | Oil & Gas Operator | Mar 2026 | |
| 6 | Hrubetz Oil Co. | Dallas, TX 75225 | Oil Operator | Sep 1986 |