Granted Patent
Utility
US 4,589,625 · App. 06/565,771
Hydraulically operated valves
Inventor:
Marvin R. Jones
Patented Case
View Patent ↗
Granted: May 20, 1986
Filed: Dec 27, 1983
Inventor
Marvin R. Jones
Assignee (at issue)
Koomey Blowout Preventers, Inc.
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.