Granted Patent
Utility
US 5,993,513 · App. 08/628,878
Method for controlling the oxygen content in valve metal materials
Inventor:
James A. Fife
Patented Case
View Patent ↗
Granted: Nov 30, 1999
Filed: Apr 5, 1996
Inventor
James A. Fife
Assignee (at issue)
Cabot 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.