Granted Patent
Utility
US 5,721,765 · App. 08/565,330
Personal identification number security system incorporating a time dimension
Inventor:
David B. Smith
Patented Case
View Patent ↗
Granted: Feb 24, 1998
Filed: Nov 30, 1995
Inventor
David B. Smith
Assignee (at issue)
LUCENT TECHNOLOGIES INC.
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.