Granted Patent
Utility
US 5,343,469 · App. 07/713,963
Communication system and communication devices having lock function
Inventor:
Izumi Ohshima
Patented Case
View Patent ↗
Granted: Aug 30, 1994
Filed: Jun 11, 1991
Inventor
Izumi Ohshima
Assignee (at issue)
NEC 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.