Seoul Viosys v expert e-Commerce & Anor (UPC_CoA_762/2024 & UPC_CoA_773/2024)
Decision date:
05 November 2025
Osborne Clarke summary
- Seoul Viosys (SV) is the owner of a patent for LED technology (EP 320). This patent is a divisional application of a European Patent application (the parent application or EP 598 A2). The parent application is the European regional phase of a Korean PCT application, which claims priority from three Korean applications.
- SV started infringement proceedings in the Düsseldorf LD and expert counterclaimed for revocation. The court held EP 320 invalid for added subject-matter, rejected the requests for amendment of the patent and dismissed the infringement action. SV appealed this decision.
- The Court of Appeal first acknowledged that the parties agreed on who the skilled person was before applying the claim interpretation principles from Nanostring v 10x Genomics.
- In interpreting features 1.2 and 3 of claim 1, the Court of Appeal agreed with SV. At first instance, the Düsseldorf LD took the view that claim 1 one was limited to one mesa, basing its opinion on the use of the singular in feature 4.1, according to which the reflective electrode is to be arranged on the mesa. However, the Court of Appeal disagreed, noting that "the mesa" in feature 4.1 merely means that at least one reflective electrode is arranged on at least one mesa. The Court of Appeal also considered the use of "comprehensive" at the beginning of claim 1 to suggest that the LED may have other elements, such as additional mesas with additional electrodes. The Court of Appeal therefore considered that "one" mesa be regarded as indefinite within the meaning of "at least one" and that the term "one mesa" in the patent claim refers to the presence of at least one mesa and thus includes embodiments with multiple mesas.
- Despite siding with SV on claim construction, the Court of Appeal went on to addressed the first instance decision on added matter. The Düsseldorf LD found that the earlier applications did not disclose an LED with a single mesa. The Court of Appeal rejected SV's procedural objection that the Düsseldorf LD had raised this view independently and without prior notice for the first time at the oral hearing. The Court of Appeal held that the finding was based on SV's own arguments and discussed during oral proceedings. The Court of Appeal ultimately disagreed with SV that Figures 24 to 26 showed a clear and unambiguous disclosure of a LED with a single mesa.
- As the patent in dispute was a divisional, there is added matter if the subject matter of the patent extends beyond the application as originally filed or beyond the content of the parent application as originally filed. In this case, the parent application was the regional phase of a PCT application, which was in the Korean language. The Court of Appeal stated that if an international application is not written in one of the official languages of the EPO, the content of the earlier application is determined primarily on the basis of a translation.
- Contrary to SV's view, this is not a purely formal or procedural requirement. The translation filed by an applicant is presumed accurate as it is in the applicant's interest that the examination be based on the true content of the application. The parties and the court can therefore rely prima facie on the accuracy of the translation.
- SV argued that the translation filed was incorrect and submitted a corrected translation. The Court of Appeal held that if an applicant considers the translation incorrect and wants to rely on a corrected version, it must prove the inaccuracy and that, based on the corrected translation, the subject matter of the patent does not extend beyond the content of the earlier application. Merely submitting a corrected translation is not enough. In any event, the Court of Appeal did not find convincing SV's arguments as to why the corrected translation better reflected the content of the earlier application.
- The Court of Appeal concluded that the first instance finding of invalidity based on added matter (a claim directed to an LED with only one mesa went beyond the content of the earlier application) was correct. The auxiliary requests all related to embodiments with a single mesa and therefore could not lead to a valid claim. The infringement claim was not considered in light of the invalidity finding. As such, SV's appeal was dismissed and SV was ordered to bear the costs of the appeal proceedings.
Issue
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