Granted Patent
Utility
US 4,261,504 · App. 06/077,548
Heat-sealable, ovenable containers
Inventor:
David A. Cowan
Patented Case
View Patent ↗
Granted: Apr 14, 1981
Filed: Sep 21, 1979
Inventor
David A. Cowan
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.