Merck Sharp Dohme Corp & Anor v Teva Pharma BV & Anor

A quia timet patent claim requires an averred and provable threat and intention to infringe. The inference depends on all the circumstances; no universal probability or imminence test applies. Obtaining a marketing authorisation is not itself infringement, but its timing may evidence an intended pre-expiry launch. Silence may support an inference when considered with that evidence, though silence alone is insufficient. A properly pleaded claim should not be struck out merely because the precise launch date is unknown. Interim relief may be granted where there is an arguable threat of pre-expiry infringement and the launch would cause substantial, unquantifiable harm.

The claimants sought an interim injunction restraining the defendants from marketing generic efavirenz in alleged infringement of a UK patent and supplementary protection certificate. The defendants sought strike-out under CPR Pt 3 r 3.4(2)(a), arguing that obtaining a marketing authorisation and declining to disclose launch plans disclosed no reasonable grounds for alleging a threat.

The court considered whether the pleaded facts supported a quia timet claim and, separately, whether interim relief was justified before trial. The central issues were the significance of a marketing authorisation obtained 22 months before expiry, the defendants’ refusal to state their intentions, commercial confidentiality, and the relevance of prior conduct and European decisions.

1. Strike out. The strike-out application was dismissed. A quia timet claim requires a threat and intention to infringe, but the court declined to impose an all-encompassing test for how those matters must be proved. The assessment depends on the facts and all relevant circumstances, with justice between the parties as the aim (paras [30]-[39]).
2. Obtaining a marketing authorisation does not itself infringe the patent, consistent with Upjohn v Kerfoot [1988] FSR 1 and section 60(5)(i) of the Patents Act 1977. Nevertheless, obtaining it 22 months before expiry provided a substantial basis for inferring an intended launch before expiry. The defendants’ general evidence did not displace that inference (paras [43]-[51]).
3. The threshold for jurisdiction and strike out was distinct from whether an interim injunction was immediately needed. The absence of evidence of a launch within the next few weeks did not defeat the properly constituted action. The claim could be tried promptly and a final injunction would remain available if the threatened infringement were proved (paras [52]-[58]).
4. For interim relief, the court applied the American Cyanamid approach. The defendants’ silence was not treated in isolation. In the context of the marketing authorisation and its timing, it was legitimate to infer that they were unwilling to wait for the proceedings before launching. Commercial confidentiality did not prevent that inference (paras [59]-[72], [81]-[86]).
5. The European decisions showed only that evidence of a threat is required and that each case turns on its facts. The Düsseldorf analysis was accepted: a marketing authorisation alone does not establish launch timing, but timing may support an inference. The interim injunction was granted, supported by the claimants’ cross-undertaking in damages (paras [73]-[87]).