Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6061456 | Noise cancellation apparatus | Douglas Andrea | 2000-05-09 |
| 5825897 | Noise cancellation apparatus | Douglas Andrea | 1998-10-20 |
| 5732143 | Noise cancellation apparatus | Douglas Andrea | 1998-03-24 |
| 5715321 | Noise cancellation headset for use with stand or worn on ear | Douglas Andrea | 1998-02-03 |
| 5673325 | Noise cancellation apparatus | Douglas Andrea | 1997-09-30 |
| 5381473 | Noise cancellation apparatus | Douglas Andrea | 1995-01-10 |