Granted Patent
Utility
US 6,149,407 · App. 09/317,732
Gas-venting domestic hot water circulation pump
Inventor:
Karsten Laing
Patented Case
View Patent ↗
Granted: Nov 21, 2000
Filed: May 24, 1999
Inventor
Karsten Laing
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.