Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6005951 | Electronic stethoscope | James A. Grasfield, David E. Winston, John Purbrick, Peter R. H. Stark | 1999-12-21 |
| 6002777 | Electronic stethoscope | James A. Grasfield, David E. Winston, John Purbrick, Peter R. H. Stark | 1999-12-14 |
| 5825895 | Electronic stethoscope | James A. Grasfield, David E. Winston, John Purbrick, Peter R. H. Stark | 1998-10-20 |
| D389575 | Chestpiece of a stethoscope | James A. Grasfield, David E. Winston, Peter R. H. Stark | 1998-01-20 |
| D389576 | Stethoscope | James A. Grasfield, David E. Winston, Peter R. H. Stark | 1998-01-20 |
| D389577 | Housing element of a stethoscope | James A. Grasfield, David E. Winston, Peter R. H. Stark | 1998-01-20 |
| D389241 | Binaurals of a stethoscope | James A. Grasfield, David E. Winston, Peter R. H. Stark | 1998-01-13 |