Granted Patent
Utility
US 4,979,539 · App. 07/313,938
Sanitary mixing valve
Inventor:
Hans-Josef Rohr
Patented Case
View Patent ↗
Granted: Dec 25, 1990
Filed: Feb 23, 1989
Inventor
Hans-Josef Rohr
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.