Granted Patent
Utility
US 4,379,946 · App. 06/265,484
Signalling system and signal control equipment for multi-address calling
Inventors:
Toshiro Mizuno, Kazuo Imai
Patented Case
View Patent ↗
Granted: Apr 12, 1983
Filed: May 20, 1981
Inventors
Toshiro Mizuno
Kazuo Imai
Assignee (at issue)
Nippon Telegraph and Telephone Public 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.