Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10049688 | Method for handling on-hold music during telephone connection and corresponding communication device | Anton Werner Keller, Rolf Guldener | 2018-08-14 |
| 9398150 | Method of setting detection parameters in an apparatus for on hold music detection | Anton Werner Keller, Rolf Guldener | 2016-07-19 |