Granted Patent
Utility
US 6,138,913 · App. 08/981,859
Security document and method using invisible coded markings
Inventors:
Michael John Cyr, James J. Krutak, Horst Clauberg, Tony Wayne Helton
Patented Case
View Patent ↗
Granted: Oct 31, 2000
Filed: Jan 5, 1998
Inventors
Michael John Cyr
James J. Krutak
Horst Clauberg
Tony Wayne Helton
Assignee (at issue)
Isotag Technology, Inc.
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.