UPC CoA clarifies urgency requirement for PIs - five key principles
On 2 July, the Court of Appeal of the UPC (“CoA”) handed down its decision in the PI proceedings between Guardant Health, Inc. (“Guardant”) and Sophia Genetics SA et al. (“Sophia”). Both parties appealed the decision of the Local Division Paris (“LD Paris”) of 23 January 2026. Although Guardant successfully objected to the finding that the patent was likely invalid for added matter, the CoA held that the urgency requirement was not met and therefore no PI was granted.
What preceded
Guardant is the proprietor of EP 3 443 066 (“EP 066”), which claims a method for detecting the presence or absence of colorectal, ovarian, lung or pancreatic cancer. EP 066 was granted on 2 October 2024 and claims priority of 14 and 18 April 2016. No opposition was filed. In addition to its UPC designation, EP 066 is in force in CH, ES and the UK. Sophia offers the MSK-DDM test in the UPC territories, CH, ES and NO.
On 27 May 2025, Guardant sent a warning letter to Sophia arguing that the MSK-DDM test falls within the scope of several patents, but not mentioning EP 066. Sophia replied on 20 June 2025. On 14 July 2025, Guardant started litigation in the UK for infringement of the UK parts of several patents, including EP 066. It lodged its reasons on 18 August 2025.
On 29 August 2025, Guardant applied for a PI before the LD Paris for the alleged infringement of several patents, including EP 066. The LD Paris held that the urgency requirement was met, but that EP 066 was likely to be invalid for reasons of added matter and therefore rejected a PI. Guardant appealed the order regarding EP 066 and costs; Sophia lodged a cross-appeal.
Assessment of the CoA – urgency
The CoA held that the assessment of unreasonable delay depends on the circumstances of the individual case. The decisive point in time is when the applicant has, or should have had, after exercising due diligence, the necessary facts and evidence. The burden of proof rests on the applicant. The CoA found that Guardant acted with unreasonable delay based on the following five principles:
1) A patent holder is not obliged to assert all patents in one application for a PI. If a patent holder has the necessary information for some, but not all patents, delaying the filing until it has information regarding all patents may constitute unreasonable delay. The CoA considers it compatible with procedural efficiency and the frontloaded system to file multiple separate applications weeks apart before the same division, since asserting multiple patents in a single application carries the risk that a prompt decision cannot be expected.
2) If a patent holder is aware, on the basis of a certain document, that one or more of its patents have been infringed, it must not turn a blind eye to the fact that the document also indicates the infringement of its other patents. The fact that the warning letter did not concern EP 066 does not justify the conclusion that Guardant was unaware of the infringement of EP 066.
3) While a patentee is generally not obliged to monitor the market, it must investigate the market with due diligence once it becomes aware of specific circumstances suggesting infringement. As soon as Guardant was aware of infringing activities in the UK, it was expected to investigate whether infringement occurred in the UPC territory, CH and ES.
4) For legal entities, the decisive factor is when the authorised representative body or an individual capable of pursuing the infringement internally becomes aware of the possible infringement (e.g. an employee of the legal department or a senior member of the sales department). The fact that other employees attended Sophia’s online seminars is insufficient, as they were not involved in evaluating potential patent infringement claims and had no obligation to forward information to decision makers.
5) As a general rule, a patent holder may wait a reasonable time for a response to a warning letter before drafting and lodging an application for a PI. However, since the warning letter did not concern EP 066, there was no reason for Guardant to wait for Sophia’s response before drafting an application regarding EP 066.
Based on a certain document, the CoA concludes that Guardant (should have) had knowledge of the alleged infringement of the MSK-DDM test by 1 May. All information Guardant further relied upon was publicly available, requiring no substantial investigative measures. A diligent patentee could have completed this inquiry within two weeks, making 15 May 2025 the latest date on which Guardant should have been aware of the infringement in the UPC territory, CH and ES. Therefore, leaving a three-months’ gap from 15 May 2025 until 29 August 2025 for submitting the PI application, while Guardant stated it needed two weeks for drafting, is unreasonable. The patent’s complexity, technical tests and expert consultation do not justify the delay: Guardant failed to specify when the analyses began, for which patents they were essential, their duration or why the delay was reasonable. Even assuming the tests took a month, a two-months delay remained unaccounted for.
Conclusion
This decision provides a comprehensive guidance on urgency required for PIs in the UPC. The CoA establishes that a patentee: 1) need not assert all patents in one application and must not delay filing once it has sufficient information for some; 2) must not ignore infringement of other patents indicated in a document it has reviewed; 3) must investigate infringement in other designated territories once aware of infringement in one; 4) is deemed aware only when the authorised representative body or an individual capable of pursuing the infringement internally becomes aware of it and 5) may wait for a response to a warning letter, but not if that letter did not concern the patent at issue. As Guardant failed to meet these principles, no PI was granted.