Granted Patent
Utility
US 6,554,992 · App. 08/485,081
Aluminum alloy exterior coating for underground ductile iron pipe
Inventor:
W. Harry Smith
Patented Case
View Patent ↗
Granted: Apr 29, 2003
Filed: Jun 7, 1995
Inventor
W. Harry Smith
Assignee (at issue)
MCWANE, 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.