Granted Patent
Utility
US 4,454,913 · App. 06/222,537
Safety valve system with retrievable equalizing feature
Inventors:
Shelby L. Guidry, Kerry D. Jernigan
Patented Case
View Patent ↗
Granted: Jun 19, 1984
Filed: Jan 5, 1981
Inventors
Shelby L. Guidry
Kerry D. Jernigan
Assignee (at issue)
Schlumberger Technology 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.