Granted Patent
Utility
US 4,450,074 · App. 06/408,088
Control of anaerobic filter
Inventor:
Shinya Ochiai
Patented Case
View Patent ↗
Granted: May 22, 1984
Filed: Aug 13, 1982
Inventor
Shinya Ochiai
Assignee (at issue)
Celanese GmbH
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.