Granted Patent
Utility
US 4,297,880 · App. 06/119,041
Downhole pressure measurements of drilling mud
Inventor:
Eugene Berger
Patented Case
View Patent ↗
Granted: Nov 3, 1981
Filed: Feb 5, 1980
Inventor
Eugene Berger
Assignee (at issue)
General Electric 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.