Granted Patent
Utility
US 5,474,127 · App. 07/989,752
Annular safety system for oil well
Inventor:
Pat M. White
Patented Case
View Patent ↗
Granted: Dec 12, 1995
Filed: Dec 14, 1992
Inventor
Pat M. White
Assignee (at issue)
Halliburton
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.