Granted Patent
Utility
US 6,769,221 · App. 09/855,635
Stairway system
Inventor:
Robert H. Green
Patented Case
View Patent ↗
Granted: Aug 3, 2004
Filed: May 14, 2001
Inventor
Robert H. Green
Assignee (at issue)
ECMD, 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.