Micron has filed a lawsuit in the U.S. District Court for the District of Idaho against YMTC. The company alleges that YMTC recruited former Micron engineers to misappropriate 3D NAND manufacturing trade secrets and technology, subsequently using these to build a patent portfolio used in counter-litigation against Micron.
The lawsuit identifies several former employees, including Daesik Song, Wenxi Zhou, and Hua Tan, who allegedly accessed sensitive server data at Micron's Boise facility. Micron claims these individuals failed to disclose their new employment at YMTC, which prevented the company from realizing that proprietary technical information had been compromised.
The dispute centers on critical 3D NAND manufacturing processes, including high-aspect-ratio etching, gate replacement, and multi-layer stacking. Micron argues that YMTC utilized these former employees to develop patents that overlap with their previous work at Micron, effectively converting trade secrets into YMTC's intellectual property.
This legal action follows a series of global patent disputes initiated by YMTC since November 2023, spanning the U.S., China, Germany, and the UK. To date, the parties are involved in over 20 legal proceedings, including patent infringement claims and challenges to patent validity.
In September 2026, the Munich Regional Court ruled that Micron infringed on two German utility models held by YMTC. Micron has appealed this decision, which involved patents linked to former Micron engineer Wenxi Zhou, further intensifying the global conflict over 3D NAND technology ownership.
