Granted Patent
Utility
US 4,553,233 · App. 06/562,133
Multiple-ring communication system
Inventors:
Pierre L. Debuysscher, Hugo J. P. Peeters, Christiaan G. M. M. Hennebel
Patented Case
View Patent ↗
Granted: Nov 12, 1985
Filed: Dec 16, 1983
Inventors
Pierre L. Debuysscher
Hugo J. P. Peeters
Christiaan G. M. M. Hennebel
Assignee (at issue)
International Standard Electric 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.