Granted Patent
Utility
US 5,352,409 · App. 08/078,603
Buffer and method for buffering hot tubs and spas
Inventor:
David J. Kierzkowski
Patented Case
View Patent ↗
Granted: Oct 4, 1994
Filed: Jun 17, 1993
Inventor
David J. Kierzkowski
Assignee (at issue)
Great Lakes Biochemical Company, Inc.
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.