Expired Canadian patentCanada
Method of increasing the filling capacity of tobacco
CA 680461 A · Owner: Imperial Tobacco Company Of Canada · Inventors: Rice, Robert L.; Desouza, John E.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordRead 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
- Granted February 18, 1964. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 18, 1981.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJuly 18, 1961
GrantedFebruary 18, 1964
Term endedFebruary 18, 1981
Patent numberCA 680461 A
Classification (IPC)A24B9/00 +1 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.