Granted Patent
Utility
US 5,555,484 · App. 08/222,042
Electromagnetic door holder system
Inventors:
William P. Dye, Paul J. Hoggard
Patented Case
View Patent ↗
Granted: Sep 10, 1996
Filed: Apr 4, 1994
Inventors
William P. Dye
Paul J. Hoggard
Assignee (at issue)
Von Duprin LLC
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.