韓國股市暴跌，本週已觸發第二次交易暫停

By Kwanwoo Jun and Megan Cheah

South ​Korean shares slumped more than 8%, prompting regulators to halt trading for the second time this week as jitters over the valuations of companies riding the artificial-intelligence boom rattled the world's best-performing market this year.

The benchmark Kospi tumbled 8.1% Friday afternoon, erasing Thursday's gains as investors grew concerned that the rapid growth in profits of chip manufacturers that supply the AI industry could top out. Reflecting how volatile trading of South Korean stocks has become, regulators briefly suspended trading again in an effort to steady the market.

SK Hynix and Samsung Electronics, which have been dueling for the title of South Korea's most valuable company and account for more than 50% of the Kospi's market value, suffered sharp reversals on Friday, extending a rollercoaster run that has seen them swing more like meme stocks. Nvidia supplier SK Hynix slumped 9.2% and Samsung fell 7.7%.

Some analysts have pinned the severity of declines by the Kospi on rampant speculation from individuals and traders using borrowed money to turbocharge bets. In a bearish development, Apple raised the prices of its Macs and iPads early Thursday morning, unsettling investors who are concerned it could sap demand for chips.

The selloff reached other Asian markets anchored by large semiconductor companies that have hit record highs this year on the AI boom. Japan's Nikkei Stock Average declined 4.8%, led lower by a 13% drop in the share price of SoftBank Group, which is seen as a proxy for the AI trade.

Analysts pointed to a report that ChatGPT maker OpenAI is considering delaying its initial public offering.

In a report on Thursday citing sources familiar with the matter, the New York Times said OpenAI is leaning toward holding off its IPO until next year due to concerns around market volatility.

OpenAI didn't immediately respond to a request for comment sent on Friday. News Corp, owner of The Wall Street Journal and Dow Jones Newswires, has a content-licensing partnership with OpenAI.

Capital Economics expects the AI rally that has lifted stocks to be reaching its last stage, as the surge has become concentrated in select stocks and dependent on continued rapid growth in earnings. Still, stocks likely still have room to rise this year before sharply declining next year, it said.

Within individual markets, tech-heavy ones including South Korea and Taiwan could continue to outperform peers as long as the U.S. capital-expenditure boom continues, it said. "The recent volatility of the Korean market illustrates the sensitivity of tech share prices to news around, and perceptions of, the ongoing capex surge," said Capital Economics.

Friday's selloff in Korea came after the Kospi gained 5.4% and 3.3% in the two preceding trading sessions, respectively. Blockbuster earnings from Micron in the U.S. midweek appeared to have steadied nerves among investors, but the calm proved fleeting.

The local market was "under pressure to lock in short-term profits following the previous days' sharp rise," Kiwoom Securities analyst Han Ji-young said in a note. Han pointed to mixed signals overnight from the U.S., where the Nasdaq fell 0.5% but the Dow Jones Industrial Average rose 0.1%.

In a sign of the toll market volatility is exacting, the stock-exchange operator has postponed the launch of options for four blue-chip stocks amid concerns that the market has overheated.

Weekly options tied to shares of Samsung Electronics, SK Hynix, Hyundai Motor and LG Energy Solution had been due to be listed next Monday.

--Sherry Qin contributed to this report.

Write to Kwanwoo Jun at kwanwoo.jun@wsj.com and Megan Cheah at megan.cheah@wsj.com

(END) Dow Jones Newswires

June 26, 2026 02:22 ET (06:22 GMT)

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