Granted Patent
Utility
US 4,479,112 · App. 06/379,755
Secure input system
Inventor:
Steven B. Hirsch
Patented Case
View Patent ↗
Granted: Oct 23, 1984
Filed: May 19, 1982
Inventor
Steven B. Hirsch
Assignee (at issue)
Secure Keyboards Limited
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.