Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8353705 | Attendance tracking system | Douglas Ahlers, Bernie DiDario | 2013-01-15 |
| 5385515 | Start ratio engagement control system and method | Kwok W. Chan | 1995-01-31 |
| 4795495 | Sewer cleaning device | — | 1989-01-03 |