Granted Patent
Utility
US 4,512,770 · App. 06/461,350
Liquid drainage system with anti-reflux valve
Inventors:
James P. Cianci, Terry N. Layton
Patented Case
View Patent ↗
Granted: Apr 23, 1985
Filed: Jan 27, 1983
Inventors
James P. Cianci
Terry N. Layton
Assignee (at issue)
The Kendall Company LP
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.