Granted Patent
Utility
US 5,323,874 · App. 08/117,420
Combination ladder and stair
Inventors:
Mitchell R. Warren, Daniel J. Dittberner, Grant M. Strawcutter
Patented Case
View Patent ↗
Granted: Jun 28, 1994
Filed: Sep 7, 1993
Inventors
Mitchell R. Warren
Daniel J. Dittberner
Grant M. Strawcutter
Assignee (at issue)
Soft Play, 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.