Issued Patents All Time
Showing 1–12 of 12 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6671744 | Access control method for drive units, and a drive unit using the method | Masahiro Ito | 2003-12-30 |
| 6477653 | Information storage system | — | 2002-11-05 |
| 6370647 | Information storage system | — | 2002-04-09 |
| 6199148 | Method and apparatus for preventing unauthorized use in systems having alternative control for avoiding defect areas on recording media | — | 2001-03-06 |
| 5982886 | Unauthorized use preventing method for optical disks, optical disk having unauthorized use prevention function, and optical disk apparatus | Satoshi Itami, Kenichi Utsumi, Masahiro Nakada, Hiroshi Suzuki, Kazuo Nakashima +2 more | 1999-11-09 |
| 5930825 | Method and apparatus for preventing unauthorized use by comparing medium identifications | Kazuo Nakashima | 1999-07-27 |
| 5809300 | Removable storage medium and computer system using the same | Kenichi Utsumi, Koichi Ogawa, Makoto Yoshioka, Satoshi Itami, Kazuo Nakashima | 1998-09-15 |
| 5684785 | Optical disk and method of preventing fraudulent use of optical disk rotation synchronous control system | Satoshi Itami, Kenichi Utsumi, Kazuo Nakashima, Satoshi Komura | 1997-11-04 |
| 5661800 | Method and manufacture for preventing unauthorized use by judging the corresponding relationship between logical and physical addresses | Kazuo Nakashima | 1997-08-26 |
| 5422871 | Method and apparatus for producing an optical disk having a read-only area and a rewritable area | Kazuo Nakashima, Kenichi Utsumi | 1995-06-06 |
| 5418852 | Unauthorized use prevention method for optical disks, optical disk having unauthorized use prevention function, and optical disk apparatus | Satoshi Itami, Kenichi Utsumi, Masahiro Nakada, Hiroshi Suzuki, Kazuo Nakashima +2 more | 1995-05-23 |
| 5402339 | Apparatus for making music database and retrieval apparatus for such database | Kazuo Nakashima, Masahiro Nakada, Toshikatsu Narumi | 1995-03-28 |