Granted Patent
Utility
US 5,625,681 · App. 08/514,196
Method and apparatus for telephone number portability
Inventor:
George Butler
Patented Case
View Patent ↗
Granted: Apr 29, 1997
Filed: Aug 11, 1995
Inventor
George Butler
Assignee (at issue)
Stratus Computer, 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.