Granted Patent
Utility
US 5,116,416 · App. 07/593,999
Boron-treated hard metal
Inventors:
Jack D. Knox, Donald C. Pennington, Jr.
Patented Case
View Patent ↗
Granted: May 26, 1992
Filed: Oct 9, 1990
Inventors
Jack D. Knox
Donald C. Pennington, Jr.
Assignee (at issue)
Vermont American 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.