Granted Patent
Utility
US 4,215,640 · App. 06/075,293
Buttonhole stitch method
Inventor:
Donald J. Coughenour
Patented Case
View Patent ↗
Granted: Aug 5, 1980
Filed: Sep 12, 1979
Inventor
Donald J. Coughenour
Assignee (at issue)
The Singer Company Limited
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.