Method and device for calculating computer file signatures
CA 2120294 C · Owner: Ugon, Michel · Inventors: Ugon, Michel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a process for the signature of a main computer file (FP) of the type consisting in having the circuits of an information processing device (1 3, 4) calculate at least one signature (SG) for the file based on at least one secret datum (S; Sd) proper to the signatory but unknown to the signatory, stored in a secret memory zone of a portable electronic object (4) with processing circuits and memory, available to the said signatory and in relating the said calculated signature to the main file. It is distinctive in that during the calculation of each signature it consists also in taking into account at least one part of the main file so that the signature is based on …
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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 March 30, 1994 and granted February 23, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 30, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 30, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.