Granted Patent
Utility
US 4,859,987 · App. 07/131,907
Apparatus and method for monitoring liquid levels
Inventor:
James A. Markus
Patented Case
View Patent ↗
Granted: Aug 22, 1989
Filed: Dec 11, 1987
Inventor
James A. Markus
Assignee (at issue)
CASCO PRODUCTS 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.