Apotex moved to file an amended Responding Statement of Issues on a reference pursuant to Rule 153. According to the Court, Apotex wants to argue that the Plaintiffs are not entitled to any damages for infringement of their patent because, after issuance of the liability judgment against Apotex and exhaustion of Apotex’s appeals, but before the hearing of the damages reference, the Supreme Court of Canada rendered a decision in another proceeding rejecting one of the principles upon which the trial judge relied in finding that the Plaintiffs’ patent had been validly issued. Apotex also seeks leave to allege that the Plaintiffs have breached specific provisions of the Competition Act, such as to disentitle them to damages.
The Court held that the essence of the amendments were a collateral attack on the ruling that Apotex infringed a valid patent. Both res judicata and issue estoppel were found to prevent Apotex from re-opening the question of validity, as that question was finally determined as between the parties. Since a change in the law was not found to be sufficient reason to re-open a previously decided case, there was insufficient reason to allow the amendment.
As for the claims sought to be added pursuant to the Competition Act, those were found to be better decided in a separate action, and not grafted onto a damages reference.