KOSPI fell more than 3 percent Friday as losses in U.S. technology stocks and concerns over returns on artificial intelligence (AI) investments triggered selling in heavyweight chipmakers Samsung Electronics and SK hynix. The benchmark index ended at 5,730.74, down 206.92 points, or 3.48 percent. It opened 2.99 percent lower at 5,760.35 and extended its losses during the session. The sharp sell-off in KOSPI 200 futures triggered a sell-side sidecar at around 10:05 a.m., temporarily halting program sell orders. It was the first such activation in 11 trading sessions, following KOSPI’s 7.57 percent plunge on Oct. 15. Samsung Electronics lost 3.02 percent, while SK hynix dropped 7.08 percent. The declines followed earnings releases from U.S. technology giants that raised fresh doubts about the returns on their massive AI investments. Google parent Alphabet reported weaker-than-expected results and a wider free cash flow deficit. Amazon’s earnings and guidance also fell short of forecasts, drawing attention to the costs of expanding AI infrastructure. Wall Street’s three major indexes cl