Granted Patent
Utility
US 4,926,292 · App. 07/391,459
Broadband printed spiral
Inventor:
Marshall Maple
Patented Case
View Patent ↗
Granted: May 15, 1990
Filed: Aug 9, 1989
Inventor
Marshall Maple
Assignee (at issue)
Avantek, 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.