Granted Patent
Utility
US 6,435,538 · App. 09/362,651
Stair chair
Inventors:
Jonathan Stewart Ellis, Philip Ian Ward
Patented Case
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Granted: Aug 20, 2002
Filed: Jul 27, 1999
Inventors
Jonathan Stewart Ellis
Philip Ian Ward
Assignee (at issue)
Ferno-Washington, INC.
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.