Issued Patents All Time
Showing 1–7 of 7 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8221586 | Security substrate comprising watermark | — | 2012-07-17 |
| 7483188 | Security device | Brian William Holmes | 2009-01-27 |
| 6199911 | Security element for security paper | Roland Isherwood | 2001-03-13 |
| 5447335 | Security device and authenticatable item | — | 1995-09-05 |
| RE33802 | Numbered documents | Colin J. Whitehead, Robin Bratchley | 1992-01-21 |
| 4645240 | Numbered documents | Colin J. Whitehead, Robin Bratchley | 1987-02-24 |
| 4296326 | Watermark detection | Reginald G. Knapman, Michael A. West | 1981-10-20 |