Granted Patent
Utility
US 6,370,241 · App. 08/997,363
Telephony system for calling card calls
Inventor:
Theresa Clark
Patented Case
View Patent ↗
Granted: Apr 9, 2002
Filed: Dec 23, 1997
Inventor
Theresa Clark
Assignee (at issue)
Quest Communications Int'l., 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.