Press Release
29 July 2025

Zhuhai CosMX Battery Co., Ltd., alongside its subsidiary Zhuhai CosMX POWER Co., Ltd., have achieved a substantial success in patent nullity proceedings brought before the German Federal Patent Court against the German part of European Patent EP 3 627 606 B1, related to an electrolyte composition used in lithium-ion-batteries. The patent is held by Ningde Amperex Technology Limited (ATL).

At the hearing on 15 July 2025, the Court followed CosMX’s evidence-based novelty attacks, resulting in a revocation of the patent as granted, and upheld the patent only in a significantly narrowed form, based on an auxiliary request of ATL. This latest outcome marks an important development in limiting the scope of the ATL patent.

Under the findings of the court, in order to overcome the prior art on evidence ATL had to limit the wording of the patent claim in a manner that under the court’s logic excludes the presence of a particular dinitrile (succinonitrile, or SN, also known as butane-1,4-dinitrile) from the claimed composition. SN is a component, however, that is commonly used in such electrolytes, as evidenced in the prior art. The remaining commercial relevance of the patent can thus be considered to be significantly limited. 

The result, which is appealable as of right for both parties, can be regarded as a key strategic success in the ongoing international dispute between CosMX and ATL which has currently pending infringement and validity litigation also in China and in the US, where the parallel US patent has been invalidated already as result of a jury trial. The implications of last week’s partial invalidity finding in Germany on the pending infringement appeals before the Higher Regional Court of Munich are under evaluation. In March 2024 the Munich Regional Court had found that Zhuhai CosMX Battery Co., Ltd. and several affiliated companies had infringed the patent as originally granted by supplying certain battery models. The hearing of the infringement appeals is scheduled for March 2026. CosMX continues to vigorously defend its position in all jurisdictions and is currently considering its options regarding an appeal of last week’s invalidity decision to the German Federal Court of Justice with the goal to have the German part of the patent revoked in its entirety.

CosMX is represented in this case by Dr Michael Schneider (Attorney-at-law), Dr Martin Nohlen (Patent Attorney), Dr Peter Wiegeleben (Patent Attorney), 
Dr Uwe Stilkenböhmer (Patent Attorney), Philipp Rastemborski, LL.M. (Attorney-at-law) and Lukas Wosnitza (Attorney-at-law).