Granted Patent
Utility
US 6,182,218 · App. 08/881,533
Digital content management system using electronic watermark
Inventor:
Makoto Saito
Patented Case
View Patent ↗
Granted: Jan 30, 2001
Filed: Jun 24, 1997
Inventor
Makoto Saito
Assignee (at issue)
MITSUBISHI CORPORATION
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.