Granted Patent
Utility
US 4,838,731 · App. 07/092,764
Septic tank distribution box system
Inventor:
Norman W. Gavin
Patented Case
View Patent ↗
Granted: Jun 13, 1989
Filed: Sep 3, 1987
Inventor
Norman W. Gavin
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.