Granted Patent
Utility
US 6,098,656 · App. 09/440,077
Check valve
Inventor:
Alfred J. Farina
Patented Case
View Patent ↗
Granted: Aug 8, 2000
Filed: Nov 15, 1999
Inventor
Alfred J. Farina
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.