Issued Patents All Time
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D320618 | Writing and drawing instrument | — | 1991-10-08 |
| D319844 | Ball point pen | Friedrich Heger | 1991-09-10 |
| D319845 | Mechanical pen | Friedrich Heger | 1991-09-10 |
| 4981383 | Device for screwing a writing instrument tip into a writing fluid reservoir | Karl Kaiser | 1991-01-01 |
| 4892428 | Tip removal device | — | 1990-01-09 |
| D303992 | Retractable holder for an eraser or similar article | — | 1989-10-10 |