Granted Patent
Utility
US 4,554,976 · App. 06/494,038
Test tool for subsea blowout preventer stack
Inventors:
Joseph H. Hynes, Charles D. Morrill, George D. Hall
Patented Case
View Patent ↗
Granted: Nov 26, 1985
Filed: May 12, 1983
Inventors
Joseph H. Hynes
Charles D. Morrill
George D. Hall
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.