Granted Patent
Utility
US 4,634,152 · App. 06/727,491
Casing hanger running tool
Inventor:
John Pettit
Patented Case
View Patent ↗
Granted: Jan 6, 1987
Filed: Apr 26, 1985
Inventor
John Pettit
Assignee (at issue)
Vetco Offshore Industries, 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.