Granted Patent
Utility
US 6,711,238 · App. 09/235,529
Parallel-connected dialing signal transmission inhibiting device for data transfer over a telephone link
Inventors:
Frank B. Manning, William Hume Vance
Patented Case
View Patent ↗
Granted: Mar 23, 2004
Filed: Jan 22, 1999
Inventors
Frank B. Manning
William Hume Vance
Assignee (at issue)
ZOOM Telephonics, 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.