System and method for preventing delivery of unsolicited and undesired electronic messages by key generation and comparison
CA 2660288 C · Owner: Kim, Leslie J. · Inventors: Cunningham, Brian; Kim, Leslie J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A sending device prepares a key for each electronic message sent by the device by applying an algorithm to specified data in the message and then incorporates the key in the message. A receiving device upon receipt of an electronic message, locates the incorporated key and the data from which a sending device practicing the invention would have prepared it. The receiving device communicates a confirmation request to the purported sending device which contains the key and the data for its preparation. The sending device receives the confirmation messages and prepares a comparison key by applying the algorithm to the data in the confirmation request. The sending device replies to the …
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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 August 9, 2005 and granted June 10, 2014. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 9, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.