Klaka and Gulde defend Oppo against KPN in Düsseldorf

KPN had accused Oppo’s German sales company of infringing EP 2 377 337 with its 5G-capable mobile devices, particularly smartphones. The company sought an injunction from the Düsseldorf Regional Court to ban Oppo device sales in Germany. However, the judges under presiding judge Carsten Haase disagreed (case ID: 4b O 44/22).

The Düsseldorf patent judges ruled that the decisive claim 12 is not infringed by Oppo devices and dismissed KPN’s lawsuit. In April 2025, the Federal Patent Court upheld the patent with restrictions. The judgment has since become final, so the infringement proceedings focused solely on whether claim 12 was infringed.

Although Oppo had invoked a FRAND compulsory licence during proceedings, FRAND played only a minor role in the oral hearing as judges expressed early doubts about claim 12 infringement.

The panel also included Stephan Janich and judge Schröder. KPN can appeal against the judgment at the Higher Regional Court Düsseldorf, which observers consider likely. The appeal could see renewed scrutiny of Oppo’s FRAND behaviour.

Oppo to take portfolio licence

The lawsuit does not affect 5G-capable devices from the OnePlus brand, as the Oppo subsidiary already holds a licence for KPN’s SEP portfolio.

KPN has previously taken action against other implementers, with those proceedings now settled according to JUVE Patent sources, though details remain private. The disputes included German proceedings against Xiaomi, while Sony had filed oppositions at the EPO against individual KPN patents.

KPN aims to have Oppo accept a similar portfolio licence. To this end, the Dutch mobile company has also sued Oppo’s German sales company for infringing a second patent, EP 2 291 033, at Düsseldorf Regional Court (case IDs: 4b O 27/22).

The Regional Court has stayed proceedings pending the outcome of Oppo’s revocation action against EP 033, currently before Germany’s Federal Court of Justice.

The patent is also under pressure in the Netherlands, where a company named Verify IP has challenged EP 033. In July, the District Court The Hague invalidated the Dutch part of the patent (case ID: C/09/642293 / HA ZA 23-131). An appeal is still possible. The Dutch ruling indicates that Verify IP is a company founded by Oppo with the aim of invalidating the patent in the Netherlands.

Early SEP battle at the UPC

The dispute has also reached the UPC, though JUVE Patent is not aware of lawsuits regarding the related patents in other jurisdictions outside Germany, the Netherlands, and the Unified Patent Court.

At the UPC, KPN has targeted Oppo’s parent company in two lawsuits. The first, filed in September 2024, alleged infringement of EP 2 387 844 (case ID: ACT_49159/2024 and UPC_CFI_502/2024). However, in December 2024 the EPO Boards of Appeal declared EP 844 invalid due to added subject matter (case ID: T1841/23).

KPN filed a second UPC suit in January 2025, alleging various Oppo companies infringe EP 2 337 403 with their mobile devices (case ID: ACT_53784/2024). Both actions are before The Hague local division under presiding judge Edger Brinkman and Margot Kokke.

Klaka and Gulde for Oppo

For the German proceedings at Düsseldorf Regional Court, Oppo retained lawyers from Klaka and patent attorneys from Gulde & Partner. Constantin Kurz, currently still a Klaka partner, led the infringement proceedings. His firm is experiencing significant departures, with Kurtz expected to join CMS Hasche Sigle by year’s end.

Martin Thimm handled technical aspects of the infringement dispute. He is a partner at Berlin patent attorney firm Gulde & Partner, known for its Asian implementer relationships. The firm represents Oppo in some EPO oppositions, while Hoffmann Eitle patent attorneys handle others.

Krieger Mes has long represented KPN in German proceedings, with partner Axel Verhauwen leading. For the Düsseldorf actions, he worked alongside patent attorney Nazim Söylemezoglu from Cologne IP firm Bayer-Vorberg-Kayser.

UPC counsel

Bird & Bird filed the UPC suits together with patent attorneys from Amsterdam firm De Vries & Metman. Both firms maintain long-standing relationships with the Dutch telecommunications company. The Bird & Bird team includes Amsterdam partners Peter van Gemert and Tjibbe Douma, plus counsel Carlos van Staveren.

Patent attorney Erik Visscher from De Vries & Metman joins the UPC team. He also leads KPN’s EPO opposition proceedings where Xiaomi and Oppo challenge EP 844’s validity.

Rien Broekstra from Dutch firm Brinkhof heads the Vossius & Brinkhof UPC Litigators team representing Oppo at the UPC. Brinkhof has previously represented Oppo in disputes against Panasonic, Nokia, Sisvel and KPN.