The Central Division Paris on patent amendments and revocation – Defense based on an embodiment (“variant”) of a non-attacked claim admissible!

Introduction
On 29 July 2024, the Unified Patent Court's Central Division in Paris issued a significant decision regarding the revocation action of European patent number EP 3 414 708, which pertains to technologies for cold chain monitoring of perishable goods. The action was initiated by Bitzer Electronics A/S against Carrier Corporation.

Main Points of the Decision
The court ruled that amendments proposed by the patent proprietor to claims that were not under direct challenge in the revocation action are inadmissible. Interestingly, however, the court recognized the patent proprietor's right to amend challenged claims by incorporating (in the present case: all) features from non-challenged claims. This again means that, a defense of the challenged claim as based on a “variant”, i.e. embodiment, of a non-attacked claim is possible. 

This presents an interesting contrast to the judgment of the German Federal Court of Justice on March 3, 2017 (judgment of March 3, 2017 - X ZR 10/15 - Ankopplungssystem). According to the Federal Court of Justice, a patent can only be defended to the extent that it is challenged by the revocation claimant. A restricted defense of an attacked patent claim by combination with a non-attacked patent claim or with one of several “variants” of a non-attacked claim (i.e. a non-attacked claim with further features, e.g. based on the description) is not permissible. 

On the procedural front, the Central Division dismissed several "new grounds" as being late-filed. However, in this particular case, these "new grounds" were not among those specified in Article 138 EPC. Instead, they were actually “new lines of argumentation”. One instance involved an additional line of argumentation against novelty, which was initially raised in response to a prior art document introduced within an inventive step attack. This argument was introduced relatively early in the proceedings, specifically alongside the immediate response to the claim amendment. Another "new ground" involved an inventive step attack based on a document initially introduced as novelty-destroying vis-a-vis the granted claim. This line of argument was also presented concurrently with the immediate response to the respective claim amendment.

Key takeaways

• The court ruled that while amendments to unchallenged claims are inadmissible, the patent proprietor can amend challenged claims using (all) features from non-attacked claims (even if this in effect an amendment of an unchallenged claim…).
• This decision contrasts with German Federal Court of Justice practice, which limits defense strategies to only the challenged claims and which does not allow (full) incorporation of non-attacked claims.
• Handling of Late-filed Arguments: The court dismissed several "new grounds" for invalidity as late-filed; a “new ground” in this sense being a “new line of argumentation”.