| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | O'Brien Energy Resources Corp | Portsmouth, NH 03801 | Oil & Gas Operator | Oct 2025 |
| 2 | Oil Internationa | Oil Operator | Jun 1986 | |
| 3 | Oil Producers, Inc. Of Kansas | Wichita, KS 67206 | Oil & Gas Operator | Oct 2025 |
| 4 | Oil Property Management, Inc. | Attica, KS 67009 | Oil & Gas Operator | Feb 2021 |
| 5 | Omega Enterprise | Oil Operator | Sep 1990 | |
| 6 | Oxford Explorati | Oil & Gas Operator | Mar 1993 |