Suinno Mobile & AI Licensing v Microsoft (CoA, 29 June 2026)

Dhenne Avocats · 19 October 2026

Our analysis

Summary

The standing judge of the Court of Appeal refused Suinno leave to appeal, under Rule 221 RoP, the cost decision of the Paris Central Division of 31 March 2026, which had awarded Microsoft EUR 300,000 out of a claimed EUR 360,940.60 following the revocation proceedings in UPC_CFI_433/2024. The order states that the review of a cost decision on appeal is limited to a marginal review of whether the assessment compensates the successful party beyond what is reasonable and proportionate, and found no such deviation, the award being within the EUR 600,000 ceiling applicable to the EUR 5,000,000 case value.

Why it matters

The order clarifies the very narrow gateway for appealing UPC cost decisions: leave under Rule 221 RoP will not be granted merely because the losing party disputes the quantum, and arguments extraneous to the cost assessment, here allegations of misrepresentation, were held irrelevant to cost proceedings. The marginal review standard means that the real battle over recoverable costs takes place before the judge-rapporteur at first instance, where the necessity and reasonableness of each activity must be substantiated. Parties should therefore treat the first instance cost procedure as effectively final in the ordinary case and budget accordingly, particularly where the value of the dispute sets a high ceiling.

Practical point

Contest the reasonableness and proportionality of individual cost items exhaustively before the judge-rapporteur. An appeal will not reweigh the assessment.

Summary prepared by Dhenne Avocats. Only the official text of the decision is authoritative.