Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11454014 | Combination toilet and urinal | — | 2022-09-27 |
| 5141157 | Vandal resistant locking device for pop-up sprinkler nozzle housings | Joseph Han, Hendrik Amirkhanjan | 1992-08-25 |
| 4681259 | Rotary drive sprinkler | Edward M. Troup, Giles A. Kendall, Joseph Han, Calvin A. Gongwer | 1987-07-21 |