Granted Patent
Utility
US 5,041,998 · App. 07/444,582
Digital video mixer
Inventors:
Frank S. Lawrence, Raymond Blackham
Patented Case
View Patent ↗
Granted: Aug 20, 1991
Filed: Nov 30, 1989
Inventors
Frank S. Lawrence
Raymond Blackham
Assignee (at issue)
GRASS VALLEY LIMITED
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.