Granted Patent
Utility
US 4,972,503 · App. 07/391,136
Method and apparatus for determining audience viewing habits by jamming a control signal and identifying the viewers command
Inventor:
Everett Zurlinden
Patented Case
View Patent ↗
Granted: Nov 20, 1990
Filed: Aug 8, 1989
Inventor
Everett Zurlinden
Assignee (at issue)
A.C. Nielsen Company
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.