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Expired Canadian patentCanada

Automatic telephone systems

CA 468357 A · Owner: Leich Electric Company · Inventors: James M. Blackhall; Alexander C. Reid

CIPO record

Overview

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Its claims, description and drawings are in the Canadian Patents Database.

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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted September 26, 1950. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 26, 1967.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedSeptember 26, 1950
Term endedSeptember 26, 1967
Patent numberCA 468357 A
Classification (IPC)H04Q1/14

Timeline

Timeline From CIPO dates

195119531955195719591961196319651967Patent grantedSep 26, 1950Term endedSep 26, 1967

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.