Granted Patent
Utility
US 4,768,229 · App. 06/887,311
Restrictive access control system
Inventors:
Lester F. Benjamin, Gopalan Krishnamurthy, Jouke N. Rypkema
Patented Case
View Patent ↗
Granted: Aug 30, 1988
Filed: Jul 21, 1986
Inventors
Lester F. Benjamin
Gopalan Krishnamurthy
Jouke N. Rypkema
Assignee (at issue)
Zenith Electronics 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.