South Korean Chip Stocks Sink as Memory Selloff Expands

South Korean chip stocks fell on October 13, 2026, as SK Hynix and Samsung Electronics extended losses after new memory technology progress from China’s CXMT raised competition concerns across the global semiconductor market.

According to finance.yahoo.com, South Korea’s benchmark KOSPI dropped 6%, while SK Hynix and Samsung Electronics each declined about 8%. The two companies account for more than half of South Korea’s stock market capitalization.

The decline followed CXMT’s announcement of progress on a memory-cell design intended to increase storage capacity in less physical space. The company plans to launch a new server memory product using the architecture by the end of 2026.

According to finance.yahoo.com, Samsung Electronics, SK Hynix, and US-based Micron together control about 90% of the global DRAM market. The companies have benefited from rising demand for memory and storage chips linked to artificial intelligence data center expansion.

Micron and SK Hynix were expected to open lower on Tuesday after the global memory-chip selloff continued. The overnight trading session reflected activity before regular markets reopened.

Finance.yahoo.com reported that all three major memory makers reached $1 trillion valuations during the summer as investors focused on artificial intelligence demand. Samsung later reported a preliminary record third-quarter profit forecast of $80 billion.