Mr Justice Meade recently handed down judgment in the ongoing Neurim v Mylan  (now named Viatris) saga. This judgment followed an expedited three-day trial of preliminary issues (see "Neurim v Mylan: Take Two"). Dealing predominately with the principles of issue estoppel, abuse of process and competition law issues, this judgment is also notable for imposing a new duty on parties to litigation before the Patents Court to keep it informed about scheduling issues and changes to hearing dates in parallel EPO proceedings, regardless of whether they intend to make case management applications themselves.

The issue arose out of the complex fact pattern in this dispute. Mr Justice Marcus Smith had held Neurim's patent to be valid and infringed by Mylan in a December 2020 judgment. The patent was revoked by the EPO Opposition Division prior to the UK trial but Neurim had appealed, thus suspending the effect of that first instance decision. Following the UK trial and following a final order hearing (but before agreement of the form of wording for the final order in the UK proceedings) Neurim withdrew its appeal at the EPO (the TBA having indicated at oral proceedings that it would find the patent invalid for insufficiency). The patent was therefore revoked ab initio,  including the UK designation.

Neurim also had a divisional patent in prosecution and, following its grant in June 2021, began further proceedings against Mylan in the UK.

Towards the end of the judgment in the new proceedings (at paragraph 181), Mr Justice Meade commented on the procedural situation, noting that a good deal of complexity, confusion and use of resources could have been avoided if the original UK trial for the parent patent had been scheduled after the TBA hearing.

Indeed, Mr Justice Marcus Smith had already pointed out this issue "with characteristic courtesy and restraint" in his consequentials judgment handed down in March 2021 (which we wrote about in " Going out with a Bang, what a difference 2 days makes: Neurim v Mylan"). Without criticising the parties' actions, Marcus Smith J noted that the parties' conduct had effectively prevented the court from considering whether a stay was or was not appropriate.

Mr Justice Meade added the following (emphasis added):

"...I strongly agree with him. As he said, the parties probably had their own strategic reasons for wanting to keep the UK trial date once they knew the date of the TBA hearing, and perhaps they would have persuaded the Court that that was the right course had they brought the situation to its attention. However, what is clear is that they should have kept the Court actively and fully informed. The Court might have wanted to make its own decision to put the UK trial a little later in case (as turned out) the EPO revoked the Patent and made it unnecessary. This is an important lesson for the future and parties in litigation in the Patents Court where there are parallel EPO proceedings should regard themselves as under a duty to inform the Court about scheduling issues and scheduling changes, whether or not they intend to make a case management application themselves and whether or not it suits their strategy."

Mr Justice Meade has therefore now formalised the position by imposing a duty on the parties to keep the Court informed on developments at the EPO. This has clear implications on parties involved in managing parallel proceedings across multiple jurisdictions. It appears that a clear and dedicated communication to court might be required, depending on circumstances. In Neurim v Mylan there was a mention of the TBA hearing in Mylan's skeleton for the pre-trial review but Marcus Smith J rejected this as insufficient to bring the matter appropriately to the court's attention.

Furthermore, with the recent news that the Unified Patent Court will soon be up and running (see our update in "The Unified Patent Court comes back to life") pan-European patent litigation will soon be in a state of flux. That being the case this may be the first in a series of new issues that must be factored into the management of such litigation. The UK court's approach to parallel proceedings at the UPC will necessarily be different, seeing as UPC decisions will not be binding on the UK court, but the UPC is likely to be an increasingly important player in the patent system.

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