Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D399978 | Paving element | Fritz von Langsdorff, Harald von Langsdorff | 1998-10-20 |
| 5360285 | Set of shaped stones and shaped stone for paving ground areas with wide gaps therebetween | Fritz von Lansdorff, Harald von Langsdorff | 1994-11-01 |
| 5342142 | Angular paving stone for paving areas | Fritz von Langsdorff, Harald von Langsdorff | 1994-08-30 |
| 4834575 | Paving stone | Fritz V. Langsdorf | 1989-05-30 |