CHINA’S leading flash memory maker Yangtze Memory Technologies Co. (YMTC) has filed a lawsuit against its U.S. rival Micron Technology, alleging infringement of eight of its patents.

The civil lawsuit against the largest U.S. memory chip maker and its unit Micron Consumer Products Group was filed Thursday at the U.S. District Court for the Northern District of California.

According to the lawsuit, Micron turned to YMTC’s patented technology to fend off competition from YMTC and to gain and protect market share. It said Micron was not paying its fair share to use the patented inventions.

The products named in the suit include YMTC’s 96-, 128-, 176- and 232-layer NAND flash memory chips, South China Morning Post said yesterday.

“While we cannot discuss the specifics of pending litigation, I can confirm that YMTC recently filed a lawsuit in the U.S. District Court for the Northern District of California against Micron Technology for infringement of our company’s patents related to the design, manufacture, and operation of 3D NAND technology,” YMTC said yesterday.

“We are confident that this matter will be resolved swiftly.”

NAND chips store data in devices such as smartphones and personal computers and at data centers for the likes of Amazon, Facebook and Google. How many gigabytes of data a phone or laptop can hold is determined by how many NAND chips it includes and how advanced they are.

Micron, the last company producing memory chips in the United States, makes DRAM chips and NAND flash memory chips and competes with South Korea’s Samsung Electronics and SK Hynix as well as Japan’s Kioxia, a unit of Toshiba.

Founded in 2016, YMTC is a rising power in manufacturing NAND chips and the 7-year-old Chinese firm unveiled in August last year its first 232-layer 3D NAND chip, the state-of-the-art X3-9070.

TechInsights, a company that analyzes and tracks the flash memory market, concluded that YMTC was the leader in the 3D NAND flash memory sector, outpacing Micron.

YMTC said in the U.S. indictment that it is no longer a new market entrant but has become a significant player in the global 3D NAND market.

YMTC’s expansion and low-price offerings present “a direct threat” to Micron, the White House wrote in a June 2021 report, which described YMTC as China’s “national champion.”

YMTC’s international rise was disrupted in October 2022 when the United States updated its trade rules, which not only further restricted China-bound chipmaking equipment, but also prevented U.S. persons from providing maintenance on such equipment in the country.

After being added to Washington’s so-called Entity List, YMTC delayed the construction of a second wafer fab in Wuhan and slashed equipment orders.

The company regained its footing in March when it received a US$7 billion capital injection from investors to keep producing NAND memory chips without support from American suppliers.

The U.S. measures have so far not derailed YMTC’s progress. The firm has forged closer ties with domestic suppliers such as Naura to replace U.S. parts in its manufacturing equipment.

The company also recently manufactured what by some measures is the “world’s most advanced” 3D NAND memory chip known to be in a consumer device, according to TechInsights, which called it a “surprise technology leap.”

YMTC said the lawsuit was meant to end Micron’s widespread and unauthorized use of its patented innovations, according to a report by Chinese business news portal Yicai.com. (SD-Agencies)