Granted Patent
Utility
US 4,239,082 · App. 06/023,061
Multiple flow valves and sidepocket mandrel
Inventor:
Ben D. Terral
Patented Case
View Patent ↗
Granted: Dec 16, 1980
Filed: Mar 23, 1979
Inventor
Ben D. Terral
Assignee (at issue)
Camco 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.