Granted Patent
Utility
US 4,201,893 · App. 05/946,699
Private automatic branch exchange telephone system with two data sources sharing a multiplexed data bus
Inventor:
Donald W. McLaughlin
Patented Case
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Granted: May 6, 1980
Filed: Sep 28, 1978
Inventor
Donald W. McLaughlin
Assignee (at issue)
GTE Automatic Electric Laboratories, Incorporated
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.