Kospi loses 3.52%, erasing Wednesday's gains as chip stocks face profit-taking
Key Facts
South Korea's Kospi index closed Thursday, October 22, 2026, down 3.52% at 5,533.77 points, according to Yonhap News Agency, as selling resumed in major chip stocks. The agency attributed part of the decline to profit-taking after the market rebounded in the previous session. The index had ended Wednesday up 3.29% at 5,735.66 points. By Thursday's close, the Kospi had erased that rebound's gains and returned to a level below Wednesday's close. The reversal came amid persistent concerns over the financing and profitability of AI investments, which weighed on Asian technology stocks during the week.
During Thursday's session, Samsung Electronics shares fell 4.03%, according to Yonhap. SK Hynix shares posted a larger decline of 5.49%, with both stocks falling more than the broader index. The agency linked selling in major chip stocks to investors taking profits following the previous session's gains. Pressure on Asia's technology sector had already emerged on Tuesday, before Lam Research reported results on Wednesday. Investing.com attributed that pressure at the time to "renewed concerns over the financing and profitability of the AI boom," in a context broader than the reaction to any single company's results.
Against the backdrop of the sector's moves, Lam Research said in its earnings release on Wednesday that revenue for the quarter ended in September reached $8.22 billion. Its official results table showed revenue rose 22% from the previous quarter ended in June, while adjusted diluted earnings per share on a non-GAAP basis were $2.20. Korea accounted for 20% of the company's revenue in the September quarter, highlighting the Korean market's presence in its business. Chief Executive Tim Archer said "AI is driving semiconductor demand higher and increasing device complexity." Nevertheless, the company's shares fell 6.25% to $244.50 in after-hours trading following the results, according to Investing.com.
Looking ahead, Lam Research forecast revenue of $8.60 billion for the December 2026 quarter in its statement. The company set a range of plus or minus $400 million around that level. The midpoint of the guidance range exceeds the revenue the company recorded in the September quarter. In Korea, SK Hynix announced that it would report its third-quarter 2026 results on October 28. The company's upcoming announcement follows Thursday's decline in its shares and marks the next date to watch for its results in the memory sector.