System and method for authenticating software carriers
CA 2175063 C · Owner: Cookson, Christopher J. · Inventors: Cookson, Christopher J.; Ostrover, Lewis S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A disk player that will play only authorized disks. Predetermined data blocks including those in the lead-in section of the disk which contain content related data, are processed to derive an authorization code. The authorization code is stored on the disk in encrypted form using the private key of a , public-key cryptosystem pair. The player processes the same disk data to derive a computed code; the player also uses the paired public key to decrypt the encrypted authorization code on the disk. Play of the disk ensues only if the decrypted authorization code matches the computed code. The same technique can be used to control not play of the disk as a whole but play in certain , …
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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 October 13, 1994 and granted December 30, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 13, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 13, 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
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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.