Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 9220988 | Inclusive rotating play device | Thomas L. Keller | 2015-12-29 |
| 8870668 | Inclusive rotating play device | Thomas L. Keller | 2014-10-28 |
| 6178927 | Gas engine | Kai Rieck, Robert Glauber, Klaus Lierz, Lars Dier | 2001-01-30 |