BARDEHLE PAGENBERG achieved an important victory for Duesenfeld GmbH (Duesenfeld) to safeguard the latter's patent portfolio: By judgement of July 14, 2026 (docket no. 7 Ni 12/24 (EP)), the 7th Nullity Senate of the German Federal Patent Court rejected a nullity action by No Canary GmbH (No Canary) against the German part of European patent 3 312 922 (EP'922) by Duesenfeld in its entirety.
The challenged patent relates to a low-temperature vacuum drying method and plays a key role in the reuse of lithium-ion batteries and the recycling of raw materials such as cobalt, nickel, and lithium. In contrast to conventional methods, Duesenfeld's method prevents the formation of dangerous hydrogen fluoride and makes the recovery of performance solvents possible – with lithium salts preserved in their original chemical form (LiPF₆). The low-temperature method reduces energy consumption and causes a favorable carbon footprint. These advantages make the method by Duesenfeld unique, which is underpinned by the fact that the company successfully implemented this innovation from idea through to commercial application: currently, three large-scale plants in Europe are at the commissioning stage.
The judgement will probably be significant beyond the nullity proceedings – in spite of the possibility of an appeal: Duesenfeld globally licenses its technology and can now enforce its patent portfolio more effectively against unlicensed competitors.
At present, appeal proceedings between Duesenfeld and No Canary are pending before the Higher Regional Court of Duesseldorf, dealing with the infringement of EP'922 by No Canary. Recently, the Higher Regional Court of Duesseldorf has issued an order to take evidence on the question of infringement. A first-instance judgement – which had rejected the infringement action – is, thus, obsolete. The fact that the legal validity of EP'922 has now been confirmed by the German Federal Patent Court will lend Duesenfeld momentum in this regard as well.
Representatives of Duesenfeld GmbH:
BARDEHLE PAGENBERG (Munich)
Prof. Dr. Tilman Müller-Stoy
(Attorney-at-Law (Rechtsanwalt), Certified IP Lawyer, Commercial
Mediator (MuCDR), UPC Representative, Partner)
Dr. Axel B Berger (German and European Patent
Attorney, UPC Representative, Partner)
Dr. Sabine Kossak (German and European Patent
Attorney, UPC Representative, European Trademark and Design
Attorney, Counsel)
Dr. Kerstin Galler (Attorney-at-Law
(Rechtsanwältin), UPC Representative, Counsel)
Dr. Markus Ackermann (German and European
Patent Attorney, UPC Representative, Senior Associate)
Dr. Jasmin Brieske (Attorney-at-Law (Rechtsanwältin),
Associate)
Gramm, Lins & Partner (Braunschweig)
Dr. Jan Manfred Plöger (German and
European Patent Attorney, European Trademark and Design Attorney,
UPC Representative, Partner)
Representatives of No Canary GmbH:
Jabbusch Siekmann & Wasiljeff (Bremen)
Johannes M.B. Wasiljeff (German Patent Attorney),
Hoyng Rokh Monegier (Munich and
Duesseldorf)
Klaus Haft (Attorney-at-Law)
Dr. Alexander Lukas (Attorney-at-Law)
Glade Michel Wirtz (Düsseldorf)
Dr. Jan Hermes (Attorney-at-Law)
German Federal Patent Court, 7th Senate (Nullity
Senate)
Pekarek (Presiding Judge)
Dr. von Hartz (Judge)
Wiegele (Judge, Dipl.-Ing.)
Dr. Deibele (Judge, Dipl.-Chem.)
Niedernhuber (Judge, Dipl.-Ing. Univ.)