Expired Canadian patentCanada
Method of leaching mineral values from oil sand tailings
CA 2135360 C · Owner: Rendall, John S. · Inventors: Rendall, John S.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of removal of valuable minerals of oil sand tailings including continuous operation of mixing said tailings with acid, curing the agglomeration and leaching of the cured agglomeration for removal of valuable minerals.
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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 8, 1994 and granted March 31, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 8, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 8, 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.
FiledNovember 8, 1994
GrantedMarch 31, 1998
Term endedNovember 8, 2014
Patent numberCA 2135360 C
Classification (IPC)C22B3/08 +2 more
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.