Decision: Cass. com., 7 january. 2026, n° 21-23.458
The French Supreme Court confirms that a trade mark may be invalidated for bad faith where it is filed with the aim of unduly extending the technical protection granted by an expired patent.
The company CeramTec GmbH specialises in the manufacture of ceramic components used, among other applications, in hip and knee prostheses. It owned a European patent relating to a specific ceramic material containing chromium oxide, which notably gave the protected product its distinctive pink colour. This patent expired on August 5, 2011, causing the invention to enter the public domain. Following the patent’s expiration, on August 23, 2011, CeramTec filed three European Union trade marks: a trade mark consisting of the colour pink, a figurative trade mark depicting a pink ball, and a three-dimensional trade mark corresponding to the shape of that pink-coloured ball. These three trade marks covered products identical to those previously protected by the patent.
Claiming that the company Coorstek Bioceramics LLC was marketing products featuring the same pink colour characteristic of its products, CeramTec brought proceedings for trade mark infringement and unfair competition. In response, Coorstek counterclaimed for the invalidation of the trade marks, arguing that they had been filed in bad faith with the objective of improperly extending the protection conferred by the expired patent.
Following a request for a preliminary ruling before the Court of Justice of the European Union (CJEU), the French Supreme Court upheld the invalidation of the trade marks on the grounds of bad-faith filing and reiterated that trade mark law cannot be used to extend a technical monopoly that should have ceased to exist.
The Court emphasized that the applicant’s intention at the time of filing is the decisive factor. It is sufficient to establish that the trade mark was filed in order to preserve a technical advantage derived from the expired patent; it is not necessary to prove that the contested trade mark right actually perpetuates the protection of such a technical solution. In the present case, at the time the trade marks were filed, the pink color was regarded by the applicant as the result of a technical solution covered by the patent, rather than as an arbitrary choice. The Court therefore concluded that the trade mark filings pursued an improper objective: maintaining a monopoly over a technical innovation that should have become freely available for use following the patent’s expiration.
As a reminder, bad faith must be assessed globally on the basis of a body of evidence, including the nature of the sign, its connection with the patent, the commercial rationale underlying the filing strategy, and the chronology of the filings. In this case, the close temporal proximity between the patent’s expiration and the trade mark filings was a key factor in establishing bad faith.
However, this decision does not call into question the possibility of combining patent and trade mark protection. Such a strategy remains permissible provided that the trade mark fulfils its essential function of indicating commercial origin rather than protecting a technical solution.
Accordingly, the EUIPO has previously held that the mere filing of a trade mark for products previously covered by an expired patent is not, in itself, sufficient to establish bad faith, as there was no evidence of a strategy aimed at excluding competitors (EUIPO Cancellation Division decision of November 15, 2013, No. 8048 C).