Granted Patent
Utility
US 6,189,384 · App. 09/073,276
Route based ultrasonic monitoring system
Inventors:
Kenneth Ralph Piety, William S. Johnson
Patented Case
View Patent ↗
Granted: Feb 20, 2001
Filed: May 5, 1998
Inventors
Kenneth Ralph Piety
William S. Johnson
Assignee (at issue)
CSI Technology Co., Ltd.
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.