YMTC secures German injunctions against Micron in 3D NAND patent dispute

This initial victory for Yangtze Memory Technologies establishes a significant legal foothold in Europe, potentially restricting Micron's ability to distribute specific 3D NAND flash memory products in the German market. As these components are foundational to hard drives and PC storage media, the injunctions could force supply chain adjustments for hardware manufacturers relying on Micron silicon. The conflict highlights the increasing use of German utility models as aggressive litigation tools due to their lack of pre-grant examination. Industry observers should monitor the UPC oral hearings scheduled for February 2027, which will determine if these injunctions expand across broader European territories.

The YMTC Micron patent dispute has grown substantially since Yangtze Memory Technologies first sued Micron in the United States in November 2023 over eight patents related to its Xtacking architecture. As of July 2026, YMTC's U.S. lawsuits had expanded to cover 27 patents and 295 patent claims, with additional filings in the U.K., the Unified Patent Court, and Germany following in October 2025. YMTC's parent company Changcun Holding and its controlled subsidiaries held 6,088 granted patents as of March 31, 2026, including 5,611 invention patents, with 3,452 domestic and 2,636 overseas patents in the portfolio.

Micron has begun retaliating with its own infringement claims. In mid-July 2026, Micron filed an infringement action against YMTC at the Regional Court Munich over EP 3 706 127, with an oral hearing scheduled for June 2027. Micron has also launched parallel UPC proceedings over EP 3 574 526 in Düsseldorf and EP 2 745 295 in Mannheim, naming computer hardware manufacturer Ultron and digital storage solution providers Lexar and Apacer Technology as defendants. The utility model strategy YMTC employed in Munich is notable because, as ip fray reported, the UPC jurisdiction and UK AI patent rulings will gain exclusive jurisdiction over EPO-granted patents when the transitional period ends in 2030, making national utility model filings increasingly important as a litigation tool.

On the U.S. appellate front, YMTC and Micron jointly stipulated to voluntary dismissal of Federal Circuit Appeal No. 2026-1110, which challenged a patentability determination involving US10950623B2 covering 3D NAND memory device formation, with each side bearing its own costs. A companion appeal, No. 2026-1596, remains active with Micron now designated as appellant. The Munich injunctions are first-instance rulings, and Micron can appeal to the Munich Higher Regional Court and request suspension of enforcement while the appeal is pending.