Copying and playing protection for digital programs
CA 2232708 C · Owner: Warner Home Video Inc. · Inventors: Ostrover, Lewis S.; Cookson, Christopher J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system and method for preventing effective copying of digital recordings. A copy-state code (Fig. 1) accompanies each recording (12) one state of which , represents that no copies at all are to be made of the recording. Compatible players (10) are designed to prevent play of any writable disk which includes a "no-copy" code. It is the inconsistency between the code and the medium containing it that causes play of the medium to be inhibited.
Read the whole patent
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 February 5, 1997 and granted August 8, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 5, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 5, 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.
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.