Granted Patent
Utility
US 4,440,981 · App. 06/444,759
Electronic hold circuit
Inventors:
Gary Grantland, Hugh S. Montgomery, Eduard F. B. Boeckmann, Larry A. Woodworth
Patented Case
View Patent ↗
Granted: Apr 3, 1984
Filed: Nov 26, 1982
Inventors
Gary Grantland
Hugh S. Montgomery
Eduard F. B. Boeckmann
Larry A. Woodworth
Assignee (at issue)
GTE Automatic Electric Incorporated
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.