Granted Patent
Utility
US 6,460,860 · App. 09/739,493
Pipe seal for cast concrete
Inventor:
Norman W. Gavin
Patented Case
View Patent ↗
Granted: Oct 8, 2002
Filed: Dec 18, 2000
Inventor
Norman W. Gavin
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.