Granted Patent
Utility
US 4,386,813 · App. 06/270,088
Current tap ground contact
Inventor:
Richard H. Griffin
Patented Case
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Granted: Jun 7, 1983
Filed: Jun 3, 1981
Inventor
Richard H. Griffin
Assignee (at issue)
International Telephone and Telegraph 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.