Granted Patent
Utility
US 4,374,526 · App. 06/230,957
Hearing faculty testing and apparatus therefor
Inventor:
David Kemp
Patented Case
View Patent ↗
Granted: Feb 22, 1983
Filed: Oct 10, 1979
Inventor
David Kemp
Assignee (at issue)
NATIONAL RESEARCH DEVELOPMENT 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.