Granted Patent
Utility
US 5,213,337 · App. 07/215,655
System for communication using a broadcast audio signal
Inventor:
Robert M. Sherman
Patented Case
View Patent ↗
Granted: May 25, 1993
Filed: Jul 6, 1988
Inventor
Robert M. Sherman
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.