Granted Patent
Utility
US 6,647,548 · App. 08/709,180
Coded/non-coded program audience measurement system
Inventors:
Daozheng Lu, David H. Harkness
Patented Case
View Patent ↗
Granted: Nov 11, 2003
Filed: Sep 6, 1996
Inventors
Daozheng Lu
David H. Harkness
Assignee (at issue)
Nielsen Media Research, 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.