LTE battle between KPN and Oppo continues

Germany’s Federal Court of Justice has finally ruled on Oppo’s challenge to the validity of KPN’s EP 2 291 033. Until now, only claim 14 of the patent had been challenged. The German Federal Patent Court had previously declared the claim invalid. KPN has now failed in its appeal to the Federal Court of Justice, which dismissed the appeal (case ID: X ZR 103/24).

KPN aims to have Oppo accept a portfolio licence. To this end, the Dutch mobile company brought proceedings against Oppo’s German sales company for infringing EP 033 at the 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.

With the infringement claim so far based mainly on claim 14, there is now no basis for KPN’s claim. However, the Dutch company may now introduce further claims into the proceedings. The Federal Court of Justice has not yet ruled on the validity of the other claims in EP 033. It is therefore likely that the German case will continue.

Parallel national case

Less than a year ago, KPN suffered an initial setback in a parallel German case. The Dutch company had accused Oppo’s German sales subsidiary of also 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 sales of Oppo devices in Germany. However, the judges disagreed (case ID: 4b O 44/22) and ruled that the decisive claim 12 was not infringed by Oppo devices. Consequently, they dismissed KPN’s lawsuit. In April 2025, the Federal Patent Court upheld the patent subject to certain restrictions.

Although Oppo had invoked a FRAND compulsory licence during these proceedings, FRAND played only a minor role in the oral hearing, as the judges expressed early doubts regarding the infringement of claim 12. KPN later appealed against the judgment at the Higher Regional Court Düsseldorf.

The international dispute

KPN and Oppo are also locked in a legal battle in the Netherlands, China, and India. In 2024, the dispute also reached the UPC. Here, KPN has brought three lawsuits against Oppo’s parent company. The first, filed in September 2024, alleged infringement of EP 2 387 844 (case ID: UPC_CFI_502/2024). However, in December 2024, the EPO Boards of Appeal declared EP 844 invalid on the grounds of added subject-matter (case ID: T1841/23).

Following this, KPN launched a new attempt by filing a second UPC lawsuit in January 2025, alleging that various Oppo companies were infringing EP 2 337 403 with their mobile devices (case ID: UPC_CFI_565/2024). Both cases were filed with the local division in The Hague.

In early 2026, a third case followed concerning infringement of EP 3 349 412. However, this time KPN opted for the local division in Düsseldorf (case ID: UPC-CFI-0000249/2026).

Klaka and Gulde for Oppo

For the German proceedings at the Federal Court of Justice and Düsseldorf Regional Court, Oppo retained patent attorneys from Gulde & Partner and lawyers from CMS Hasche Sigle. Martin Thimm handled the technical aspects of the infringement dispute. He is a partner at the Berlin-based patent attorney firm Gulde, which is known for its relationships with Asian implementers. The firm represents Oppo in some EPO oppositions. Gulde lawyer Marco Scheffler was also involved.

Constantin Kurz led the infringement proceedings. He began working for Oppo as a partner at the Munich-based firm Klaka. However, at the end of 2025, Klaka suffered significant departures, with Kurz moving to CMS Hasche Sigle.

In the UPC cases, Rien Broekstra from the Dutch firm Brinkhof heads the Vossius & Brinkhof UPC Litigators team representing Oppo. Brinkhof has previously represented Oppo in various national disputes against SEP holders.

Cohausz for KPN

On KPN’s side, Christian Rohnke appeared as a lawyer admitted to the Federal Court of Justice. Patent attorneys Matthias Waters, Martin Rütten, and Lisanne Laudenberg from Düsseldorf-based firm Cohausz & Florack provided support. Koenraad Wuyts, head of the KPN’s patent department, was also present in the German courtroom.

Krieger Mes has long represented KPN in German proceedings, led by partner Axel Verhauwen. He is also leading the newly filed UPC case at the Düsseldorf local division.

However, the Dutch Bird & Bird partners Peter van Gemert, Tjibbe Douma and Carlos van Staveren are leading the cases at the local division The Hague. Patent attorney Erik Visscher from De Vries & Metman has joined the UPC team. He is also leading KPN’s EPO opposition proceedings, in which Xiaomi and Oppo are challenging the validity of EP 844.