Granted Patent
Utility
US 4,991,588 · App. 07/434,590
Doppler guide wire
Inventors:
D. Russell Pflueger, Cliff N. Cottonaro, Scott M. Evans
Patented Case
View Patent ↗
Granted: Feb 12, 1991
Filed: Nov 13, 1989
Inventors
D. Russell Pflueger
Cliff N. Cottonaro
Scott M. Evans
Assignee (at issue)
Pfizer Hospital Products Group, 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.