Patents per Year
Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date | Approx Value ⓘ |
|---|---|---|---|---|
| 5921047 | Building structure having prefabricated interfitting structural parts | — | 1999-07-13 | |
| 5291904 | Dorsiflexion assisting device for hemiplegics | — | 1994-03-08 | |
| 4771583 | Space divider system | Douglas C. Ball, William S. Stumpf, Gary R. Ludwig | 1988-09-20 | $263,000 |
| 4224769 | Space divider system | Douglas C. Ball | 1980-09-30 | $243,000 |