Judge Lets DRAM Antitrust Case Against Samsung, SK Hynix and Micron Proceed

A federal judge has allowed an antitrust case against Samsung, SK Hynix and Micron to move forward, finding that consumers plausibly alleged coordination over conventional dynamic random-access memory (DRAM) supply as production shifted toward AI memory.

U.S. District Judge Noël Wise, in the Northern District of California, denied the companies’ joint motion to dismiss on Nov. 14. The decision allows the proposed class action to advance; it does not determine whether the chipmakers agreed to limit supply or violated the law.

The case was filed June 25 by 17 consumers and small businesses from five states. Their complaint alleges the companies accounted for more than 91% of global DRAM revenue in the third quarter of 2025, began cutting conventional DRAM output in late 2022 and shifted capacity toward high-bandwidth memory (HBM) starting the following year.

The complaint says HBM, used for AI, takes about three to four times as much wafer area per gigabyte as conventional DDR5. It alleges conventional DRAM prices climbed 171.8% in the year through the third quarter of 2025 and 697% over 18 months, while none of the defendants expanded or announced a meaningful capacity increase.

The complaint also alleged that all three companies adopted nearly identical customer-vetting practices in January 2026. Wise found that allegation strongly supported a plausible inference of an agreement. The companies argued that AI demand explained their actions, but the alleged vetting practices came after the HBM shift was already underway.

Samsung, SK Hynix and Micron argued the case repeats DRAM II, an earlier lawsuit over alleged supply restrictions from 2016 to 2018. The Ninth Circuit upheld the dismissal in 2022. Wise found that the current complaint alleges different conduct, including production cuts, a shift toward HBM and customer-vetting practices.

Wise did not accept every theory in the complaint. She found investor remarks about supply discipline too similar to arguments rejected in DRAM II, said the complaint did not identify specific information exchanges at industry conferences, and treated the companies’ concentrated market structure as neutral.

The dispute comes amid projections that HBM will take a larger share of production. Samsung Electronics executive vice president Kim Taewoo said Sept. 29 that HBM could account for nearly 30% of global DRAM wafer capacity in 2027, up from about 20% at the time, underscoring HBM’s growing share of DRAM capacity.

The companies must answer by Dec. 7. The initial case management conference is scheduled for Jan. 12, 2027.