Granted Patent
Utility
US 4,997,691 · App. 07/257,206
Retortable container
Inventor:
Keith Parkinson
Patented Case
View Patent ↗
Granted: Mar 5, 1991
Filed: Oct 13, 1988
Inventor
Keith Parkinson
Assignee (at issue)
QuesTech Ventures, 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.