Granted Patent
Utility
US 4,949,787 · App. 07/336,012
Casing hanger seal locking mechanism
Inventors:
Norman Brammer, Philippe C. Nobileau
Patented Case
View Patent ↗
Granted: Aug 21, 1990
Filed: Apr 7, 1989
Inventors
Norman Brammer
Philippe C. Nobileau
Assignee (at issue)
Vetco Gray, LLC
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.