Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5005719 | Tamper evident optical device and article utilizing the same | Roger W. Phillips, Vernon C. Spellman, Marc A. Kamerling, Paul G. Coombs, David W. Todd +1 more | 1991-04-09 |
| 4840281 | Tamper evident optical device and article utilizing the same | Roger W. Phillips, Vernon C. Spellman, Marc A. Kamerling, Paul G. Coombs | 1989-06-20 |
| 4721217 | Tamper evident optically variable device and article utilizing the same | Roger W. Phillips, Vernon C. Spellman, Marc A. Kamerling | 1988-01-26 |