Granted Patent
Utility
US 4,728,030 · App. 06/941,832
Railway sleeper with spade-like end contours
Inventor:
William H. Hodgson
Patented Case
View Patent ↗
Granted: Mar 1, 1988
Filed: Dec 15, 1986
Inventor
William H. Hodgson
Assignee (at issue)
British Steel 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.