Granted Patent
Utility
US 4,397,661 · App. 06/324,881
Gas permeation apparatus having permeate rate controlled valving
Inventors:
Duane King, John R. O'Brien
Patented Case
View Patent ↗
Granted: Aug 9, 1983
Filed: Nov 25, 1981
Inventors
Duane King
John R. O'Brien
Assignee (at issue)
Monsanto Company
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.