Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6330323 | Enhanced overflow call processing | Louis G. Gottlieb, Cathleen Frazier, Wesley D. Rogers | 2001-12-11 |
| 6112764 | Automatic safety shutoff valve | Paul D. Engdahl | 2000-09-05 |
| 5617471 | Telecommunications system for transferring a telephone call | Wesley D. Rogers, Louis G. Gottlieb, Saleem R. Molani, Gregory W. Sedlock | 1997-04-01 |
| 5307699 | Seismic initiator for earthquake shutoff valves and the like | Paul D. Engdahl | 1994-05-03 |
| 5209454 | Automatic safety shutoff valve | Paul D. Engdahl | 1993-05-11 |
| 5144598 | Intergrating, indicating, and controlling seismometer | Paul D. Engdahl, Roland S. McGee | 1992-09-01 |
| 4684958 | Seismic displacement recorder for base-isolated structures | Paul D. Engdahl | 1987-08-04 |
| 4524700 | Opening cover for railroad cars | — | 1985-06-25 |