Granted Patent
Utility
US 6,672,855 · App. 09/740,085
Vacuum pumps
Inventor:
Michael Henry North
Patented Case
View Patent ↗
Granted: Jan 6, 2004
Filed: Dec 19, 2000
Inventor
Michael Henry North
Assignee (at issue)
The BOC Group 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.