[News] German Court Reportedly Finds Micron Infringed Two YMTC NAND Patents, Grants Injunctions
A German court has issued two injunctions against Micron after finding that the company infringed YMTC patents related to 3D NAND technology. According to ijiwei, citing Ip Fray, the Munich I Regional Court handed down the first-instance rulings in two patent infringement cases, marking the latest development in the companies’ long-running global patent dispute.
The Munich I Regional Court’s 7th Civil Chamber, presided over by Judge Dr. Oliver Schön, granted YMTC injunctions over two German utility models, a form of unexamined patent protection with a 10-year term. As noted by Ip Fray, the rulings cover DE202020006166U1, related to staircase structures in 3D storage devices (case no. 7 O 12615/25), and DE202021004551U1, covering barrier layers for word-line contacts in 3D NAND memory (case no. 7 O 12614/25).
The court adjourned three other cases involving YMTC patents covering multi-stack 3D storage devices (DE202018007011U1; case no. 7 O 12609/25), 3D storage devices (DE202022003278U1; case no. 7 O 12616/25), and 3D memory devices with deposited semiconductor plugs (EP3931868; case no. 7 O 12593/25).
The ijiwei report notes, however, that these are only first-instance rulings. Micron can appeal and may ask the Munich Higher Regional Court to suspend enforcement of the injunctions.
Patent Battle Spans Multiple Markets
The dispute dates back to November 2023, when YMTC first sued Micron in the U.S. over eight patents related to its Xtacking architecture, as ijiwei notes. YMTC later expanded its U.S. claims, saying in July 2026 that its lawsuits there had grown to cover 27 patents and 295 patent claims. The battle widened further in October 2025, when YMTC filed additional patent lawsuits against Micron in the U.S., the UK, the Unified Patent Court (UPC), and Germany.
Micron has also fought back, filing more than 20 patent invalidation challenges since 2024, along with separate litigation against YMTC in the U.S. Some of those challenges have already produced results. According to ZDNet, the U.S. Patent Trial and Appeal Board invalidated YMTC’s U.S. Patent No. 12,010,838 in September following a challenge by Micron. The report notes that Micron has sought reviews of all 27 YMTC patents involved in the companies’ U.S. litigation.
YMTC Expands Its Patent Portfolio
YMTC has steadily expanded its technology and patent portfolio alongside advances in its Xtacking architecture. According to ijiwei, the company introduced Xtacking 3.0 in 2022, becoming one of the first globally to launch 3D NAND Flash products with more than 200 layers. It followed with Xtacking 4.0 in 2024, further advancing the architecture.
Its patent portfolio has expanded alongside these developments. As of March 31, 2026, YMTC parent company Changcun Holding and its controlled subsidiaries held 6,088 granted patents, including 5,611 invention patents. Of the total, 3,452 were domestic patents and 2,636 were overseas patents, ijiwei notes.
In 2025, Changcun Holding also entered into patent cross-licensing arrangements with international industry players, allowing both sides to use certain patents held by the other. According to ijiwei, Changcun Holding’s patent service fees rose from RMB 47.93 million in 2023 and RMB 49.42 million in 2024 to RMB 70.08 million in 2025.
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(Photo credit: YMTC)
