Granted Patent
Utility
US 5,913,331 · App. 09/104,046
Check valve
Inventors:
Brad L. Noll, Kirk Johnson, Timothy Hurt
Patented Case
View Patent ↗
Granted: Jun 22, 1999
Filed: Jun 24, 1998
Inventors
Brad L. Noll
Kirk Johnson
Timothy Hurt
Assignee (at issue)
ZURN INDUSTRIES, LLC
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.