Granted Patent
Utility
US 5,779,222 · App. 08/750,036
Tapered plug valve
Inventors:
Keith J. Hollingworth, Peter Richard Jones
Patented Case
View Patent ↗
Granted: Jul 14, 1998
Filed: Nov 27, 1996
Inventors
Keith J. Hollingworth
Peter Richard Jones
Assignee (at issue)
BTR plc
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.