Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5263389 | Torque rated floating marine propeller wrench | Michael A. Karls | 1993-11-23 |
| 4789303 | Marine propeller carry handle and emergency spare kit | Roger E. Koepsel, William J. Gius | 1988-12-06 |
| 4781632 | Anti-ventilation plate | John J. Litjens, Michael A. Karls, Ronald M. Steiner, William P. Lang | 1988-11-01 |
| 4718837 | Marine drive water pump impeller | — | 1988-01-12 |
| 4642057 | Shock absorbing propeller | Richard H. Snyder | 1987-02-10 |
| 4636175 | Water inlet for outboard propulsion unit | Michael A. Karls | 1987-01-13 |
| 4392779 | Marine drive water pump | James L. Bloemers, James M. Schiek, Michael A. Karls | 1983-07-12 |