Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 9677398 | Use of ventilation air methane exhausted during mining of non-combustible ore in a surface appliance | Ronald O. HUGHES, David M. Hansen | 2017-06-13 |
| 8740310 | Mining method for co-extraction of non-combustible ore and mine methane | Larry C. Refsdal, Ronald O. HUGHES, Richard A. Hodgson, Joseph A. VENDETTI | 2014-06-03 |