Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5406540 | Optical disk recording performance | Robert Longman, Quentin J. Lister, Mark J. Broadbent | 1995-04-11 |
| 5137617 | Optical disk manufacture | Robert Longman, Jitka Brynjolffssen | 1992-08-11 |
| 5008687 | Data storage medium | Robert Longman, Michael John Abrams | 1991-04-16 |
| 4928132 | Optical data storage medium | Robert M. Pettigrew, Victor C. Humberstone, Keith Gardner, Robert Longman | 1990-05-22 |
| 4893299 | Magneto-optic data storage technique | Victor C. Humberstone, Robert M. Pettigrew | 1990-01-09 |
| 4866696 | Pre-formatted moth-eye type optical data storage member and method | Robert Longman, Philip A. Storey | 1989-09-12 |
| 4724444 | Data storage medium | Robert M. Pettigrew, Victor C. Humberstone, Keith Gardner, Robert Longman | 1988-02-09 |