Granted Patent
Utility
US 5,375,477 · App. 08/000,212
Water impurity extraction device and method
Inventors:
Norman A. Neill, David Cross
Patented Case
View Patent ↗
Granted: Dec 27, 1994
Filed: Jan 4, 1993
Inventors
Norman A. Neill
David Cross
Assignee (at issue)
SP Industries LLC
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.