Granted Patent
Utility
US 4,933,969 · App. 07/162,725
Data authentication and protection system
Inventors:
Alan Marshall, Christopher Mitchell, Graeme John Proudler
Patented Case
View Patent ↗
Granted: Jun 12, 1990
Filed: Mar 1, 1988
Inventors
Alan Marshall
Christopher Mitchell
Graeme John Proudler
Assignee (at issue)
Hewlett-Packard Company, L.P.
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.