Samsung Electronics Co., Ltd & Anor v ZTE Corporation & Ors [2026] EWHC 2235 (Pat)
This is the judgment in Technical Trial A in the proceedings between the Claimants (“Samsung”) and the Defendants (“ZTE”).
This judgment concerns the validity of patent EP(UK) 3,934,154 (“the Patent”), which is owned by Samsung, and is accepted to be essential to the 5G standard and implemented in ZTE’s 5G enabled devices. The Patent improves 5G’s ‘initial access’ process, which governs the device’s ability to locate 5G cells and enables it to start receiving information about those cells. It does so by arranging radio signals within a signal synchronisation burst set, by (i) interleaving multiplexing with wider bandwidth, and (ii) by using the DMRS (usually a pure reference signal) also to identify which block within a burst set is being received.
ZTE challenged the Patent’s validity on the basis of obviousness and lack of plausibility or technical effect.
The only disagreement between the parties as to the identity of the skilled person was the skilled person’s “focus”. Mellor J found the difference to be slight and better considered as a dispute about the scope of the CGK. In this regard, Mellor J made a finding that skilled person would follow the developments of the RAN1 working group within 3GPP in real time and therefore materials before the priority date, such as the meeting minutes, formed part of the skilled person’s CGK.
Mellor J found that the Patent was valid. He dismissed ZTE’s obviousness attacks over prior art LG 434, inter alia reasoning that ZTE’s expert evidence was subject to the risk of hindsight and lacked sufficient or convincing reasoning.
Further, ZTE’s second obviousness attack, based on a collocation between LG 434 and another piece of prior art (LG 438), failed because the invention was not a collocation at all. Rather, the integers formed a singular system because the DMRS has a dual role which is spread across two of the integers of claim 1.
Mellor J also rejected ZTE’s lack of technical contribution argument because it failed to address the claim as a whole and it would be a mistake of principle to require a technical contribution from each integer separately. It would be difficult to see how a patent conceded to be essential to the 5G standard would fail to make a technical contribution.
Accordingly, Mellor J found that the Patent was valid, essential, and infringed, and that ZTE would continue to infringe absent a FRAND licence.
Brian Nicholson KC appeared for the Claimants, instructed by Kirkland & Ellis International LLP.