UPC Brussels limits interveners’ ability to pursue independent claims

Context: 2seventy Bio sued Janssen and Legend for infringement of EP3689383, which covers  genetically modified immune cells used to treat multiple myeloma. The patent is owned by the United States federal government and exclusively licensed to 2seventy Bio. The National Institute of Health (NIH) intervened in support of 2seventy Bio, while Janssen and Legend later filed counterclaims seeking revocation of the patent and challenged 2seventy Bio’s standing to sue.

What’s new: The UPC’s Brussels Local Division (LD) has ruled that an intervener cannot use its participation in a case to pursue claims beyond those of the party it supports. The court rejected the NIH’s request to be treated as a co-claimant in 2seventy Bio’s infringement action against Janssen and Legend, holding that the UPC Rules permit only supportive intervention, not what it called “aggressive” or “principal” interventions. The NIH can therefore remain an intervener in the infringement action while separately being treated as a defendant to the companies’ revocation counterclaims.

Direct impact: The ruling leaves the NIH in a split procedural position: it remains only an intervener in 2seventy Bio’s infringement action, but is treated as a defendant to Janssen and Legend’s revocation counterclaims. More broadly, parties intervening before the UPC cannot use that status to pursue an independent litigation strategy or claims beyond those of the party they support. Any move from intervener to co-claimant or co-defendant instead depends on a separate reclassification by the court based on the circumstances of the case.

Wider ramifications: The decision clarifies the limits of intervention before the UPC and suggests that party status will remain tied to the procedural role a participant has actually chosen, even where related infringement and revocation actions are being heard together. By comparison, it also limits the reach of the Hague LD’s earlier Dolby v CPYou ruling: reclassification of an intervener remains possible, but only where the circumstances justify it rather than as an automatic consequence of becoming more deeply involved in the dispute.