The Munich Regional Court I ruled against Micron on September 18, 2026, finding the company infringed on two patents held by Chinese memory manufacturer YMTC. The court issued two injunctions related to 3D NAND production technologies, specifically concerning stepped structures and barrier layers for wordline contacts.
Micron has filed an appeal against the decision and is separately challenging the validity of the patents in question. The legal dispute between the two companies began in November 2023, when YMTC first sued Micron in the United States over the alleged unauthorized use of its Xtacking 3D NAND technology.
By July 2026, the scope of the dispute expanded to include 27 patents and 295 individual claims. Micron has responded by filing 20 petitions to invalidate YMTC patents and has initiated counterclaims in the U.S. In September 2026, the U.S. Patent Trial and Appeal Board invalidated one YMTC patent.
YMTC, founded in 2016, held an 11.8% share of the global NAND market in 2025, according to UBS data. The company is currently expanding its production capacity with one new facility ready for launch and two additional plants planned, despite ongoing U.S. export restrictions.
