| Company Name | Company Location | Company Type | Most Recent Production | |
|---|---|---|---|---|
| 1 | Mark Resources Corp | Pittsburgh, PA 15276 | Oil & Gas Operator | Dec 1993 |
| 2 | Mat Oil & Gas Exploration Inc | Indiana, PA 15701-8931 | Gas Operator | Dec 1993 |
| 3 | Medina Res Dev Co LLC | Cambridge Springs, PA 16403-3447 | Oil & Gas Operator | Dec 2023 |
| 4 | Meridian Exploration Corp. | Pittsburgh, PA 15222 | Oil & Gas Operator | Dec 2021 |
| 5 | Meridian Oil & Gas Enterprises Inc | Blairsville, PA 15717-0337 | Oil & Gas Operator | Dec 2003 |
| 6 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |