Granted Patent
Utility
US 6,005,643 · App. 08/922,701
Data hiding and extraction methods
Inventors:
Norishige Morimoto, Junji Maeda
Patented Case
View Patent ↗
Granted: Dec 21, 1999
Filed: Sep 2, 1997
Inventors
Norishige Morimoto
Junji Maeda
Assignee (at issue)
International Business Machines 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.