German court rules for YMTC in NAND patent fight, potentially curbing Micron's EU sales
A Munich court issued injunctions against Micron on two 3D NAND utility models, finding infringement of YMTC patents. The rulings, dated September 18, could restrict Micron's supply in Germany and affect the broader European NAND market. Micron denies wrongdoing, has appealed, and is separately challenging the patents' validity.
The Munich 1 Regional Court's September 18 ruling covers two specific German utility models, DE202020006166U1 and DE202021004551U1, which carry ten-year protection periods. YMTC originally filed five cases in late 2025 involving four utility models and one European patent, with the remaining cases adjourned. The injunctions remain first-instance decisions, meaning Micron's appeal to the Munich Higher Regional Court could suspend them.
This dispute traces back to 2023, when YMTC sued Micron in California over eight 3D NAND architecture patents. The conflict has since expanded into a multi-jurisdictional battle spanning over 20 patents, with cases filed in China, the U.S., the U.K., and Germany, covering infringement, invalidation, and even libel claims. Seven disputed patents have already been invalidated, while Micron continues challenging validity across multiple countries. The technology at issue, 3D NAND, stacks memory cells vertically to increase density and lower per-bit costs in storage products.
This ruling could reshape the European NAND memory market, potentially limiting Micron's ability to supply SSDs and storage components to German and broader EU customers. If upheld on appeal, the injunctions may drive up prices or create supply constraints for device manufacturers, ultimately affecting consumers purchasing smartphones, laptops, and enterprise storage. The case also signals that Chinese semiconductor firms can successfully enforce intellectual property rights in Western courts, which may influence how other memory makers approach patent licensing and cross-border legal strategy in an increasingly fragmented global chip market.