Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5394952 | Core cutting rock bit | Roger Johns, Gary R. Portwood, Charles R. Muren | 1995-03-07 |
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5394952 | Core cutting rock bit | Roger Johns, Gary R. Portwood, Charles R. Muren | 1995-03-07 |