Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5857545 | Elevator system with overlapped roped-coupler segments | David W. Barrett, George A. L. David, Ernest P. Gagnon, Richard E. Peruggi | 1999-01-12 |
| 5816368 | Elevator cars switch hoistways while traveling vertically | David W. Barrett, George A. L. David, Ernest P. Gagnon, Andrew F. Peruggi, Richard E. Peruggi | 1998-10-06 |
| D351423 | Memorandum indicator for hospitals | — | 1994-10-11 |
| 5257595 | Flag system | — | 1993-11-02 |