Expired Canadian patentCanada
Method of forming and maintaining offshore ice structures
CA 958905 A · Owner: Mobil Oil Corporation · Inventors: Fitch, John L.; Jones, Lloyd G.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
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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
- Granted December 10, 1974. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 10, 1991.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedDecember 10, 1974
Term endedDecember 10, 1991
Patent numberCA 958905 A
Classification (IPC)E21B15/02 +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.