Granted Patent
Utility
US 5,311,656 · App. 07/845,503
Keypad method of manufacture
Inventor:
Michael K. Eldershaw
Patented Case
View Patent ↗
Granted: May 17, 1994
Filed: Mar 12, 1991
Inventor
Michael K. Eldershaw
Assignee (at issue)
Mitel 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.