Granted Patent
Utility
US 5,222,120 · App. 07/513,956
Long distance telephone switching system with enhanced subscriber services
Inventors:
Clark E. McLeod, Steven J. Hogan, Kristi T. Feltz, Douglas R. Murdock, Van E. Hanson
Patented Case
View Patent ↗
Granted: Jun 22, 1993
Filed: Apr 23, 1990
Inventors
Clark E. McLeod
Steven J. Hogan
Kristi T. Feltz
Douglas R. Murdock
Van E. Hanson
Assignee (at issue)
MCI Communications 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.