Apotex Inc. v. Pfizer Ireland Pharmaceuticals (Court File No. A-371-10)


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Nature of Case:

Patent Impeachment Action - Motion to Strike Pleadings  

Successful Party:

Apotex Inc. appeal granted in part; costs to Pfizer Ireland Pharmaceuticals  

Date of Decision:

March 1, 2011  


On March 1, 2011, the Federal Court of Appeal ("FCA") partly allowed an appeal by Apotex Inc. ("Apotex") and maintained allegations of issue estoppel, collateral e­stoppel, comity and abuse of process raised by Pfizer Ireland Pharmaceuticals ("Pfizer") in its Statement of Defence in an impeachment action. Ogilvy Renault represented Pfizer at the appeal.

Pfizer had successfully obtained a prohibition order against Apotex pursuant to an application brought under the PM(NOC) Regulations in respect of Canadian Patent No. 2,163,446 (the "'446 Patent"). The prohibition order was upheld on appeal. Apotex subsequently commenced a patent impeachment action in respect of the '446 Patent raising allegations of invalidity which were almost identical to those raised in the PM(NOC) proceeding. In its Defence, Pfizer asserted that Apotex is precluded from relitigating the issue of patent validity and the findings of fact and law which were made in the PM(NOC) proceeding on the grounds of res judicata, issue estoppel, collateral estoppel, comity and abuse of process (the "Abuse Allegations").

Apotex moved to strike the Abuse Allegations from Pfizer's pleading. Prothonotary Aalto dismissed Apotex's motion. On appeal, Justice Hughes heard Apotex's motion de novo and struck the allegation of res judicata while allowing the other Abuse Allegations to remain in Pfizer's Defence. Apotex further appealed to the Federal Court of Appeal.

The FCA held that the ultimate issue of validity of the '446 Patent was not decided in the prior PM(NOC) proceeding. Consequently, the Abuse Allegations cannot apply to the ultimate question of the patent's validity. However, the FCA held that "there is scope for applying the bars of issue estoppel and abuse of process in the later proceedings to prevent the relitigation of subsidiary factual and legal issues in order to preserve judicial resources, promote the integrity of the justice system, prevent inconsistent findings, and prevent abuse." The FCA cautioned that application of these principles was discretionary and would depend upon the evidence proffered at trial.


FCA Decision: The decision will be published as Apotex Inc. v. Pfizer Ireland Pharmaceuticals, 2011 FCA 77.

FC Decision (Justice Hughes): Apotex Inc. v. Pfizer Ireland Pharmaceuticals Inc., 2010 FC 968

FC Decision (Prothonotary Aalto): Apotex Inc. v. Pfizer Ireland Pharmaceuticals Inc., 2010 FC 633