Richard Meade QC, Charlotte May QC, and James Whyte appeared for the claimants and Michael Tappin QC appeared for the defendants in this strike out application against part of the claimants’ pleaded case of patent infringement.
The claimants’ patent claimed a class of compounds that included their commercial product called dolutegravir (“DTG”) and alleged that the defendants’ drug called bictegravir (“BIC”) infringed their patent under the doctrine of equivalents. Part of the claimants’ particulars of infringement alleged that BIC was developed with the aim of maintaining the characteristics of DTG by the use of similar structural features. The defendants argued that the intentions of their scientists in developing BIC were not relevant to the test of whether a product falls within a claim under the doctrine of equivalents.
The court held that although the test for patent infringement was objective, it would not be appropriate to strike out the plea which referred to the intentions of the scientists as they could be relevant to the objective test to be applied. The application was therefore dismissed.