Granted Patent
Utility
US 5,130,810 · App. 06/935,055
Method and apparatus for processing a video signal so as to prohibit the making of acceptable videotape recordings
Inventor:
John O. Ryan
Patented Case
View Patent ↗
Granted: Jul 14, 1992
Filed: Nov 21, 1986
Inventor
John O. Ryan
Assignee (at issue)
Macrovision Corporation
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.