Granted Patent
Utility
US 4,994,178 · App. 07/314,410
Heavier-than-water pool cleaning device
Inventor:
David A. Brooks
Patented Case
View Patent ↗
Granted: Feb 19, 1991
Filed: Feb 22, 1989
Inventor
David A. Brooks
Assignee (at issue)
Oakleigh, Ltd.
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.