Granted Patent
Utility
US 4,333,577 · App. 06/186,938
Tamperproof closure
Inventor:
George V. Mumford
Patented Case
View Patent ↗
Granted: Jun 8, 1982
Filed: Sep 15, 1980
Inventor
George V. Mumford
Assignee (at issue)
Owens-Illinois 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.