Granted Patent
Utility
US 5,809,154 · App. 08/453,557
Ported loudspeaker system and method
Inventor:
Matthew Polk
Patented Case
View Patent ↗
Granted: Sep 15, 1998
Filed: May 26, 1995
Inventor
Matthew Polk
Assignee (at issue)
Britannia Investment 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.