Granted Patent
Utility
US 6,481,676 · App. 09/946,193
Expandable duct hanger
Inventor:
Richard A. Bluestone
Patented Case
View Patent ↗
Granted: Nov 19, 2002
Filed: Sep 5, 2001
Inventor
Richard A. Bluestone
Assignee (at issue)
Alan Manufacturing 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.