AI-linked chip stocks seem to plunge as South Korea’s Kospi falls more than 7%

A technology-led sell-off ripped through Asian equity markets on Thursday, October 15, after Wednesday’s hotter U.S. inflation print and a slide in AI-linked shares on Wall Street, The Guardian, Reuters, Reuters via Yahoo Finance, The Korea Herald and CNBC report. South Korea’s chip-heavy Kospi took the sharpest hit among the major benchmarks those outlets cover.

Reuters says the Kospi finished down 7.57% at 5,554.22, a six-month closing low, and that foreign investors sold a net 3.6 trillion won (about $2.68 billion). The Guardian describes South Korea’s benchmark Kospi 200 as down more than 8% overnight and closed down 8.1% at a six-month low, with circuit breakers stopping trading at various points. This desk treats Reuters’ closing print as the end-of-day figure and The Guardian’s Kospi 200 line as a related but separately labeled index reading; The Korea Herald’s −8.13% figure came at 1:17 p.m. local time, before the close.

Samsung Electronics and SK Hynix anchored the move. Closing figures from Reuters put Samsung down 9.5% and SK Hynix down 11.1% after the Philadelphia Semiconductor Index dropped 4.3% overnight, Reuters says. The Korea Herald earlier put Samsung at −10.13% to 208,500 won and SK Hynix at −11.35% to 1.26 million won, and said the rout pushed SK Hynix’s market capitalization below 1,000 trillion won, to 929.18 trillion won. Reuters’ London/Singapore wrap says Samsung plunged nearly 10% and that SK Hynix and Japan’s Kioxia each plummeted more than 11%.

Elsewhere in Asia, The Guardian and Reuters put Japan’s Nikkei 225 down about 4.9% to 5%. SoftBank’s one-day move differs by outlet: The Guardian says 10%; CNBC says 7.9%. Taiwan’s TSMC fell about 2%, The Guardian and Reuters report; Reuters says it posted record profits and cited “macroeconomic uncertainties,” while The Guardian says it reported its sixth straight quarter of profits. China’s CSI 300 slipped by as much as 2.4% to its lowest level since August 2025, The Guardian says.

On Wall Street Wednesday, CNBC says the Nasdaq fell 1.88% and the S&P 500 1.11% after September consumer prices rose 3.7% year on year, above forecasts. The Guardian ties Thursday’s producer-price jump of 6.3% year on year to fresh inflation jitters. Deutsche Bank analysts led by Jim Reid told The Guardian markets had “just had an incredibly tumultuous 24 hours, as a strong US CPI print was then followed up with mounting fears around the AI trade,” and that the CPI move showed “broad-based moves across the consumer basket,” not only energy.

CNBC says 20 of the most valuable global AI and semiconductor stocks have shed more than $1 trillion in value so far this week — a striking figure this desk could not independently recompute from the named closes alone. CNBC lists Thursday declines for Nvidia of about 2.5%, Micron about 3.5%, AMD 6%, Dell more than 8%, CoreWeave 10% and Intel about 6.5%, among others. Reuters notes CoreWeave down another 6.3% in premarket after a 15% Wednesday drop, and Oracle down 2.1% after nearly 9%.

Analysts framed the move as a cost-of-capital shock more than a sudden demand collapse. Saxo Bank’s Charu Chanana told Reuters: “The selloff in Asia looks less like a sudden deterioration in technology fundamentals and more like a repricing of the cost of capital.” Mirae Asset’s Seo Sang-young told Reuters the market “is reacting sensitively to whether capital raising will be sustainable and whether massive infrastructure investment will lead to real income, rather than revenue growth itself in AI services.” Yorkville’s Dan Ives told CNBC higher yields raise financing costs for AI builds but that “rates are a financing question, not a demand question.”

J.P. Morgan’s Mixo Das told Reuters the market “is struggling to find a new buyer” after buyback programmes at Samsung and SK Hynix ran their course, while still expecting AI stocks higher on a six- to 12-month view. Korean financial authorities held an emergency meeting and vowed a proactive response for market stability and investor protection, Reuters reports. The Guardian notes the IMF warned this week that an AI share-price correction could put global financial stability at risk and said “The consequences of an AI correction could be global,” with Asian markets most exposed after the United States.

Reuters says 10-year U.S. Treasury yields swooped back down toward 5% in their biggest daily drop in more than a year, gold rose about 1% in London, and Fed funds futures implied about a 75% chance the Fed stays on hold at its October 28 meeting, per CME FedWatch. Brent crude fell nearly 2% to about $104 a barrel, Reuters says, as traders weighed sanctions relief against Strait of Hormuz shipping attacks.

Reading note: this desk wrote from published market reports, not from exchange floors. Closing prints, mid-session snapshots and differently labeled indexes (Kospi vs Kospi 200) do not always match; later updates may revise any figure above.

Correction · Oct 15, 2026, 1:04 PM PT: An earlier version of this story said The Guardian and Reuters both report that Taiwan’s TSMC fell about 2% even after record profits. Only Reuters (via Investing.com) ties the move to “record profits” and TSMC’s “macroeconomic uncertainties” line; The Guardian says TSMC fell 2% despite reporting its sixth straight quarter of profits. The body now credits each outlet for its own wording.