Granted Patent
Utility
US 5,574,780 · App. 08/556,323
Controll of call features provided to a subscriber by a hierarchical telecommunication switch
Inventors:
Donald Lee Andruska, Liane Toy Tsai
Patented Case
View Patent ↗
Granted: Nov 12, 1996
Filed: Nov 16, 1995
Inventors
Donald Lee Andruska
Liane Toy Tsai
Assignee (at issue)
LUCENT TECHNOLOGIES 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.