Granted Patent
Utility
US 4,939,773 · App. 07/371,188
Multiple party telephone control system
Inventor:
Ronald A. Katz
Patented Case
View Patent ↗
Granted: Jul 3, 1990
Filed: Jun 26, 1989
Inventor
Ronald A. Katz
Assignee (at issue)
FIRST DATA RESOURCES, LLC.
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.