Granted Patent
Utility
US 4,944,345 · App. 07/320,965
Well device lock mandrel and running tool
Inventor:
Howard R. Mashaw, Jr.
Patented Case
View Patent ↗
Granted: Jul 31, 1990
Filed: Mar 9, 1989
Inventor
Howard R. Mashaw, Jr.
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.