Granted Patent
Utility
US 4,860,346 · App. 06/944,568
Telephone system and method operated from central office loop current
Inventor:
Regis B. Mellon
Patented Case
View Patent ↗
Granted: Aug 22, 1989
Filed: Dec 22, 1986
Inventor
Regis B. Mellon
Assignee (at issue)
Protel, Inc.
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.