FILE PHOTO: Samsung Electronics HBM4, a sixth-generation high-bandwidth memory solution for AI and HPC applications, on display during the 2025 Korea Tech Festival in Seoul, South Korea, December 4, 2025. REUTERS/Kim Hong-Ji/File Photo
Jan 14 (Reuters) - Retail investors ramped up buying of U.S. memory and data storage chipmakers in January, following 2025's strong momentum on expectations that booming artificial intelligence infrastructure demand will tighten supply and lift prices.
An acute global shortage of memory chips is forcing AI and consumer-electronics companies to fight for dwindling supplies, which is expected to support a multi-yearbacklogfor memory chip makers.
Samsung's co-CEO TM Roh described the memory chip shortage as "unprecedented" in an interview with Reuters earlier this month, echoing rivals who have warned that constraints could persist for months, if not years, as the AI infrastructure race continues to hog supplies.
Data storage device maker SanDisk, whose shares have soared about 65% so far in 2026, saw more than $7.1 million in retail inflows on Monday alone, the biggest one-day move on record, according to data from Vanda Research.
Western Digital has seen nearly $10 million in inflows in the first two weeks of January, putting it on course for the strongest monthly showing since October 2025, while Seagate Technology recorded more than $2.1 million of inflows so far this year.
2025 was a record year for U.S. retail inflows as individual investors became a major force behind the rally on Wall Street. Total flows from mom-and-pop traders for these three stocks stood at more than $117.2 million last year.
Micron Technology, one of the "Big Three" memory makers in the world alongside Samsung and SK Hynix , is up 18% so far in 2026 after rising 240% in 2025.
"Memory chips are certainly among the themes that are exciting our customers these days. It's not unusual to see No. 3 Micron positioned among the leaders, but seeing SanDisk in the No. 4 slot tells us that it is more than simply a coincidence," said Steve Sosnick, chief strategist at Interactive Brokers.
Micron and SanDisk were among the five most active stocks on Interactive Brokers' platform over the past five trading days, Sosnick said.
SanDisk, whose shares have risen nearly ten-fold since its February 2025 listing, is the biggest holding of the actively managed Roundhill Meme Stock ETF.
(Reporting by Shashwat Chauhan in Bengaluru; Editing by Tasim Zahid)
