Granted Patent
Utility
US 5,204,917 · App. 07/686,368
Modular hearing aid
Inventors:
Horst Arndt, Edward S. Kroetsch, Terrence D. Spencer, Fred J. Stork
Patented Case
View Patent ↗
Granted: Apr 20, 1993
Filed: Apr 17, 1991
Inventors
Horst Arndt
Edward S. Kroetsch
Terrence D. Spencer
Fred J. Stork
Assignee (at issue)
Unitron Industries Ltd.
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.