Granted Patent
Utility
US 6,718,314 · App. 10/217,614
Multi-purpose transaction card system
Inventors:
David Chaum, Niels T. Ferguson, Jelte Willem Jan Van Der Hoek
Patented Case
View Patent ↗
Granted: Apr 6, 2004
Filed: Aug 12, 2002
Inventors
David Chaum
Niels T. Ferguson
Jelte Willem Jan Van Der Hoek
Assignee (at issue)
Info Space, 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.