Granted Patent
Utility
US 4,241,879 · App. 06/008,900
Drive system for a manure spreader
Inventor:
William F. Ostergren
Patented Case
View Patent ↗
Granted: Dec 30, 1980
Filed: Feb 2, 1979
Inventor
William F. Ostergren
Assignee (at issue)
Sperry Corp.
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.