Granted Patent
Utility
US 4,487,329 · App. 06/541,469
Tamper-evident closure
Inventor:
Thomas W. Winstead
Patented Case
View Patent ↗
Granted: Dec 11, 1984
Filed: Oct 13, 1983
Inventor
Thomas W. Winstead
Assignee (at issue)
Maryland Cup 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.