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Expired Canadian patentCanada

Process of hardening and tempering cast iron

CA 83645 A · Owner: Myers, Charles Augustus · Inventors: Gilmour, William; Bradfield, Herbert Henry; Lindsay, Alexander

CIPO record

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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 October 27, 1903. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 27, 1920.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledOctober 30, 1902
GrantedOctober 27, 1903
Term endedOctober 27, 1920
Patent numberCA 83645 A
Classification (IPC)—

Timeline

Timeline From CIPO dates

190319051907190919111913191519171919Application filedOct 30, 1902Patent grantedOct 27, 1903Term endedOct 27, 1920

Sources & verification

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