Granted Patent
Utility
US 4,619,111 · App. 06/648,533
Oilfield closing device operating system
Inventor:
Jack Whiteman
Patented Case
View Patent ↗
Granted: Oct 28, 1986
Filed: Sep 7, 1984
Inventor
Jack Whiteman
Assignee (at issue)
Hydril Company
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.