Granted Patent
Utility
US 4,745,974 · App. 06/945,028
Well tool lock mandrel and handling tools therefor
Inventor:
Brian D. Higgins
Patented Case
View Patent ↗
Granted: May 24, 1988
Filed: Dec 22, 1986
Inventor
Brian D. Higgins
Assignee (at issue)
Otis Engineering Corporation
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.