Changjiang Storage Launches First Patent Challenge Against Micron in China
After years of global patent disputes, Changjiang Storage has for the first time initiated an invalidation challenge in China against Micron Technology, the US‑based memory giant. This marks a significant step in the ongoing competition between Chinese and American semiconductor companies.
Between December 3 and 4, 2025, China's National Intellectual Property Administration disclosed three cases in which Changjiang Storage (Yangtze River Storage) challenged Micron's 3D memory patents. The patents in question involve technologies such as memory arrays with vertically adjacent semiconductor structures, methods for forming three‑dimensional memory, and charge storage devices and systems.
Meanwhile, the US Patent and Trademark Office is conducting a national security review of two invalidation requests filed by Changjiang Storage against Micron's patents in the United States. On November 10, 2025, US authorities asked Changjiang Storage to explain why its applications should still be accepted despite the company being placed on the US entity list.
It is worth noting that Changjiang Storage filed its invalidation challenges in China at the end of September and October, before the United States began its national security review. This suggests the two actions are not directly connected.
Micron has also filed at least eight invalidation challenges in China against Changjiang Storage's patents. However, because China's patent office does not yet have regulations allowing such requests to be refused outright, Micron's challenges remain under review.
Yangtze River Storage, also known as Changjiang Storage, is a leading Chinese semiconductor manufacturer specializing in NAND flash memory and solid‑state drives. Founded in Wuhan, China, the company has become a key player in China's efforts to build a self‑reliant semiconductor industry. It focuses on advanced 3D NAND technology and has invested heavily in research and development to compete with global leaders like Micron, Samsung, and SK Hynix. Yangtze River Storage is backed by state‑owned enterprises and has played a central role in China's push to reduce dependence on foreign memory suppliers.
