AstraZeneca AB & Anor v Hansoh Pharmaceutical Group Company Limited & Ors

At a case management conference, a court may defer deciding a complex patent-equivalence pleading where the argument has no practical effect on the evidence and may be reformulated. The proposed amendment may be adjourned until its application to the claims in issue is properly particularised. In infringement proceedings, a product and process description is the usual starting point for defining the defendant’s case; disclosure can then be considered against that account. An intention to make an equivalent product may support an inference about its characteristics, but the ultimate question concerns the product’s objective characteristics.

AstraZeneca AB and AstraZeneca UK Limited brought patent-infringement proceedings against four Hansoh group companies. At a case management conference, the defendants sought to amend their pleading to argue that a product per se claim could be infringed by equivalence only if the products had materially the same properties in all respects and for all purposes. AstraZeneca opposed the amendment and sought wide disclosure, including laboratory notebooks and regulatory documents. The court considered whether to permit the amendment before the defendants had particularised its application to use-limited claims, and whether the defendants should first provide a product and process description.

1. The defendants’ application to amend was adjourned. The court considered the proposed product per se argument challenging and extreme, and said it might fail at trial. But it would not refuse the pleading at this stage: the argument had no practical effect on the evidence about other uses and, if rejected, might be reformulated. The court did not decide the substantive scope of equivalents for product per se claims.

2. The proposed pleading could not proceed until the defendants properly particularised how their argument applied to the use-limited claims. The defendants were also required to plead that they accepted that a patentee could never demonstrate that the products had the same properties in all respects for all purposes, and that they would not rely on specific examples at trial. The court’s initial view that the defendants’ argument might not assist on the use-limited claims was not a final determination.

3. The court directed the defendants to provide a product and process description by the proposed date. In the Patents Court, that is the normal way to address infringement. The pleading should come first, with disclosure discussed in light of what is actually sought. The defendants should have the opportunity to decide whether laboratory notebooks were needed; the claimant’s request for broad categories of underlying documents was premature. The court referred to ViiV v Gilead [2020] EWHC 615 (Pat) as guidance on the possibility of summarising development history in a product and process description.

4. The defendants’ intention to make their product equivalent could support an inference that they had succeeded, but intention and efforts to give effect to it were secondary. The ultimate question would be the objective characteristics of the product. The court did not determine infringement at the conference.