Granted Patent
Utility
US 4,726,608 · App. 06/893,576
Information bearing article with tamper resistant scratch-off opaque coating
Inventor:
Bradley W. Walton
Patented Case
View Patent ↗
Granted: Feb 23, 1988
Filed: Aug 5, 1986
Inventor
Bradley W. Walton
Assignee (at issue)
Scientific Games of California, 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.