Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5468096 | Means for securing a cover over a drainage channel | Wolfgang Arm, Jan Witt | 1995-11-21 |
| 5466091 | Surface drainage apparatus | Wolfgang Arm | 1995-11-14 |
| 5462382 | Surface drainage apparatus | Wolfgang Arm | 1995-10-31 |
| 5437516 | Surface drainage apparatus | Wolfgang Arm, Jan Witt | 1995-08-01 |