Corma Inc & Ors v Hegler Plastik GmbH & Anor

Summary judgment is inappropriate where infringement depends on disputed expert evidence and the court would need to assess the expert’s credibility without hearing cross-examination. The court may decide a case summarily where the defence or claim has no real prospect of success, but substantial doubts about an expert’s evidence do not necessarily justify judgment at that stage. In a patent case, the meaning and application of a limitation such as “essentially constant pressure” may require evidence about the invention, the allegedly infringing process and the skilled person’s understanding. Where the evidence remains realistically capable of supporting infringement, the issue should proceed to trial.

The claimants alleged infringement of a patent concerning the manufacture of double-walled corrugated thermoplastic pipes. The defendants sought summary judgment on the infringement claim after the European Patent Office amended the relevant claim by removing the alternative relating to variable, non-continuously declining pressure.

The defendants argued that the allegedly infringing process did not satisfy the amended pressure requirement and that the claimants’ expert evidence was no longer credible because the expert had changed or clarified his position. The central issue was whether those matters could properly be resolved summarily before trial.

1. The application for summary judgment was refused. The infringement claim would proceed to trial.

2. The applicable test was not disputed. The court accepted the approach in National Westminster Bank v Daniel [1993] 1 WLR 1453: the question is whether there is a fair or reasonable probability of a real or bona fide case or defence. The same principles applied under the CPR.

3. The defendants’ first ground failed because the claimants had expert evidence capable of supporting the conclusion that the Hegler Device maintained an essentially constant pressure in the relevant space, at a pressure below p1 but above atmospheric pressure. The evidence gave the claimants a realistic prospect of establishing infringement.

4. The defendants’ principal ground depended on rejecting the claimants’ expert’s evidence as wholly incredible. The court considered that the earlier reports could reasonably be read as relying on the deleted alternative of variable, non-continuously declining pressure. The explanation in the later report did not entirely resolve the difficulty, and the court had considerable doubts about whether the evidence confronted the effect of the amendment.

5. Those doubts were insufficient for summary judgment. Without hearing the expert in the witness box and subjecting the evidence to cross-examination, the court could not properly conclude that it lacked all credibility. Nor could it resolve at that stage the extent to which observed pressure fluctuations fell within “essentially constant pressure”, or whether the quality of the manufactured pipes answered that question.

The defendants’ application was therefore refused, and the matter was left for determination at trial.

The judgment records that the action had been commenced in August 2011. A trial listed for May 2013 was vacated after Warren J admitted late experimental evidence and directed further inspections and measurements. The trial was relisted for January 2014.