Granted Patent
Utility
US 5,085,443 · App. 07/529,895
Labyrinth seal
Inventor:
Robert L. Richards
Patented Case
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Granted: Feb 4, 1992
Filed: May 29, 1990
Inventor
Robert L. Richards
Assignee (at issue)
Amoco 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.