Korea's bourse operator on Friday activated a buy-side sidecar for the benchmark Korea Composite Stock Price Index (KOSPI) as the index rose sharply, led by bargain buying in semiconductor shares following the previous session's heavy sell-off. Program trading for the KOSPI-listed shares was suspended for five minutes at around 1:50 p.m., according to the Korea Exchange (KRX). After opening 1.2 percent higher, the KOSPI added 410.29, or 5.36 percent, to 8,058.38 as of 1:57 p.m. Investors snapped up semiconductor shares following reports that artificial intelligence (AI) startup Anthropic is in talks with Samsung Electronics to develop a custom AI chip. The rebound came after the index plunged 7.89 percent Thursday, dragged down by a sharp sell-off in Samsung Electronics and SK hynix amid concerns that the AI-driven rally might have peaked. A buy-side sidecar is triggered when the KOSPI 200 Futures index rises 5 percent or more for at least one minute.