SK hynix posts record quarterly profit on AI memory demand as Seoul's KOSPI jumps 6.6%

SK hynix reported revenue of 104.62 trillion won and operating profit of 83.33 trillion won for the July-September quarter, both company records, according to its earnings release on Wednesday. Quarterly revenue topped 100 trillion won for the first time, and the operating margin reached 80%. Reuters reported that the profit beat the LSEG SmartEstimate of 76.7 trillion won. The company also announced shareholder returns worth more than 100 trillion won (about $75.3 billion) for 2026, Yonhap reported.

The Nvidia supplier said virtually all of its DRAM and high-bandwidth memory (HBM) production capacity through 2029 was already sold out, according to Yonhap. The KOSPI rose 374.1 points, or 6.63%, to close at 6,012.44, with Samsung Electronics up 9.01% and SK hynix up 10.89%, and the Korea Exchange paused program buy orders for five minutes for a second straight session, Yonhap and The Korea Herald reported.

Why it matters: Memory chips for AI data centers have become a main driver of South Korea's economy, and an analyst at Yuanta Securities told Yonhap the results eased concerns that the memory chip cycle was peaking.