Granted Patent
Utility
US 6,569,404 · App. 08/465,922
Phase shift colloids as ultrasound contrast agents
Inventor:
Steven C. Quay
Patented Case
View Patent ↗
Granted: May 27, 2003
Filed: Jun 6, 1995
Inventor
Steven C. Quay
Assignee (at issue)
Amersham Health AS
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.