Granted Patent
Utility
US 6,133,853 · App. 09/126,936
Personal communication and positioning system
Inventors:
Michael L. Obradovich, John D. Pirtle, Corena Dusek
Patented Case
View Patent ↗
Granted: Oct 17, 2000
Filed: Jul 30, 1998
Inventors
Michael L. Obradovich
John D. Pirtle
Corena Dusek
Assignee (at issue)
American Calcar, 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.