Granted Patent
Utility
US 6,723,239 · App. 10/125,103
Spin-on filter element and filter head
Inventor:
Martin C. Maxwell
Patented Case
View Patent ↗
Granted: Apr 20, 2004
Filed: Apr 17, 2002
Inventor
Martin C. Maxwell
Assignee (at issue)
Parker-Hannifin Corporation
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.