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Expired Canadian patentCanada

Method for verifying the expected postal security device in a postal security device

CA 2221674 C · Owner: Ryan, Frederick W. Jr. · Inventors: Pitchenik, David E.; Ryan, Frederick W. Jr.; Cordery, Robert A.

CIPO record

Overview

Drawings and full text

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

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Abstract From the Canadian patent

A PSD has a private key which is associated with a specific public key that is stored in the host PC. The host PC sends the PSD public key private key to the PSD. If the PSD determines that the received PSD public key corresponds to its private key, the system has determined that the expected PSD is connected to the Host system and the PSD is activated to accept postal value requests from the host PC. Additionally a PSD state, identification, such as a checksum of a PSD transaction log file stored in the host may be verified by the PSD, which also has stored therein a PSD transaction log file. In this manner the PSD verifies that the PSD has performed all transactions with the host PC …

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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

  • Filed November 20, 1997 and granted October 14, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 20, 2017.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 20, 2019.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledNovember 20, 1997
GrantedOctober 14, 2003
Term endedNovember 20, 2017
Patent numberCA 2221674 C
Classification (IPC)G07B17/02 +1 more

Timeline

Timeline From CIPO dates

1998200020022004200620082010201220142016Application filedNov 20, 1997Patent grantedOct 14, 2003Term endedNov 20, 2017

Sources & verification

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