Granted Patent
Utility
US 4,451,700 · App. 06/412,079
Automatic audience survey system
Inventors:
Marvin A. Kempner, Robert E. Elder
Patented Case
View Patent ↗
Granted: May 29, 1984
Filed: Aug 27, 1982
Inventors
Marvin A. Kempner
Robert E. Elder
Assignee (at issue)
M. A. Kempner, 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.