Granted Patent
Utility
US 4,276,937 · App. 06/009,869
Well safety system
Inventors:
Michael Bozich Calhoun, Russell Irving Bayh, III, Robert E. Dutton
Patented Case
View Patent ↗
Granted: Jul 7, 1981
Filed: Feb 7, 1979
Inventors
Michael Bozich Calhoun
Russell Irving Bayh, III
Robert E. Dutton
Assignee (at issue)
Otis Engineering Corporation
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.