Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4833697 | Writing instrument for electronic counting and gravity switch reset | Fred P. Perna | 1989-05-23 |
| 4726044 | Writing instrument with solar-powered electronic counting and liquid cyrstal display | Fred P. Perna | 1988-02-16 |