Granted Patent
Utility
US 4,884,447 · App. 07/202,320
Hearing faculty testing
Inventors:
David Kemp, Peter Michael Bray
Patented Case
View Patent ↗
Granted: Dec 5, 1989
Filed: Jun 6, 1988
Inventors
David Kemp
Peter Michael Bray
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.