Granted Patent
Utility
US 4,603,740 · App. 06/645,408
Subsurface safety valve
Inventors:
Jon Edwards, Mark Carter
Patented Case
View Patent ↗
Granted: Aug 5, 1986
Filed: Aug 29, 1984
Inventors
Jon Edwards
Mark Carter
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.