SK Hynix and Micron Technology have each reached $1 trillion market capitalizations, driven by surging demand for high-bandwidth memory in AI data centers.

As of 3 p.m. ET on May 27, SK Hynix reached a market cap of $1.1 trillion and Micron Technology reached $1 trillion, both entering the trillion-dollar club.

Memory has become a critical bottleneck in AI data centers; SK Hynix and Micron supply high-bandwidth memory (HBM — layered memory that produces higher bandwidth) to GPU designers like Nvidia, and supply chains are constrained with demand effectively pre-sold for extended periods.

In 2026 alone, SK Hynix shares have risen by more than threefold, generating a roughly 230% return; Micron shares have surged 226% year to date, making it the second-best performer in the Nasdaq-100 index.

The Roundhill Memory ETF (DRAM), launched in early April with an expense ratio of 0.65%, offers exposure to Micron, SK Hynix, Samsung, Kioxia, and Sandisk, and trades at $60 as of the article's writing.