Granted Patent
Utility
US 4,878,632 · App. 07/292,838
Magnetic tape cassettes
Inventor:
William M. Carroll
Patented Case
View Patent ↗
Granted: Nov 7, 1989
Filed: Jan 3, 1989
Inventor
William M. Carroll
Assignee (at issue)
Koller Manufacturing 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.