Global AI Chip Stocks Crater as Investors Rout on Rising Rates and Profitability Doubts

Semiconductor stocks plummeted across the United States, South Korea, and Japan on October 13-15, 2026, as surging inflation and doubts about the long-term profitability of artificial intelligence infrastructure spending triggered a sharp investor retreat from the sector. The Philadelphia Semiconductor Index dropped more than 4 percent in US trading, while South Korea's KOSPI benchmark fell 5.5 percent at the close, with memory chipmaker SK Hynix sliding nearly 10 percent and Samsung Electronics declining 7 percent. Japan's Nikkei 225 index dropped more than 4 percent, with semiconductor-related stocks among the worst performers; memory chipmaker Kioxia Holdings plunged 13 percent. The selloff wiped away roughly $1 trillion in market value from semiconductor stocks globally, according to trading data.