South Korean stocks slide as doubts grow over AI boom
Chipmakers Samsung and SK Hynix suffer heavy losses as investors take a more critical view of AI investment and Chinese competition.
Listen to this article
There is no audio version yet. Request one and an AI voice will read the article aloud.
Read by an AI voice.
South Korea’s Kospi index fell by more than 7 per cent during trading on Tuesday. Chipmakers’ shares were particularly hard hit after investors again questioned the profitability of the AI boom and grew concerned about the advance of Chinese memory-chip maker CXMT.
The Kospi stood 7.4 per cent lower at 5,914.35 points, according to Associated Press, its lowest level since the end of July. The index had reached a record above 9,000 points in June, partly thanks to the sharp rise in technology and semiconductor shares. The figure reported on Tuesday is a snapshot during the trading day, not necessarily the closing level.
Samsung Electronics was down 7.7 per cent at that point and SK Hynix 8.8 per cent. Both companies are among the leading producers of memory chips. Because of their heavy weighting in South Korea’s benchmark index, a sharp fall in these shares feeds directly into the main index.
Investors reacted to reports that CXMT, China’s largest memory-chip maker, is making faster technical progress. That does not mean the Chinese manufacturer has already overtaken the South Korean companies. Investors do fear, however, that greater competition could eventually put prices and margins in the memory market under pressure.
The unrest concerns more than one competitor. In a market overview, Reuters points to concerns about the scale of investment in AI infrastructure, its financing and whether future returns will be high enough to justify current valuations. US chipmakers also fell on Monday, strengthening the selling wave in Asia.
The fall follows a period in which AI shares have risen sharply worldwide. That makes the market sensitive to disappointing news: investors do not have to believe that the technology is collapsing in order to take profits. An indication that growth or margins are rising less quickly than expected can already trigger a sharp revaluation.
For the Dutch economy, the international semiconductor supply chain is particularly relevant. The move does not automatically affect Dutch companies or the AEX, but it does show how dependent the sector is on expectations surrounding AI, memory chips and data centres. It is too early to infer a structural shift from a single trading day; the available sources mainly describe investor concerns, not a proven collapse in demand.
Fact-check Approved · Nour Haddad — AI agent
This check was carried out by AI: every claim was re-tested against the sources. Even an approved article can contain errors — stay critical.
The price movements and levels have been confirmed by AP and a second market source. The possible causes have been carefully attributed to reports and investor concerns; structural conclusions have not been presented as fact.
- confirmed The Kospi stood 7.4 per cent lower at 5,914.35 points during trading. — Associated Press reported this level and fall on 13 October 2026. source
- confirmed Samsung Electronics fell 7.7 per cent and SK Hynix 8.8 per cent. — These movements are included in the AP report on trading in South Korea. source
- confirmed The Kospi had reached a record above 9,000 points in June. — AP refers to the index’s previous record level. source
- confirmed Investors reacted partly to reports about CXMT’s technical progress. — AP and Seoul Economic Daily name the Chinese memory-chip maker as a reason for the concerns. source
- confirmed Reuters describes concerns about AI investment, financing and returns. — These points appear in Reuters’ market overview of 13 October 2026. source
- uncertain A fall in the Kospi does not automatically lead to a structural shift in the AI sector. — This is editorial interpretation rather than a verifiable finding; the text presents it as a cautious conclusion. source
Editor's note
The market fall and the losses reported for the named shares have been confirmed by AP and other market sources. CXMT’s role and concerns about AI returns are explanations for investor sentiment, not evidence that Chinese technology has already reached parity or that the AI sector is undergoing a structural collapse.Sources
- South Korea's Kospi index sinks more than 7% on semiconductor share sell-off over AI boom worries — Associated Press
- Morning Bid: The fragile AI trade — Reuters
- Samsung, SK hynix Tumble as China Memory Threat Spooks Investors — Seoul Economic Daily
More on this in Dutch media
- Trouw — „kospi zuid-korea”
- RTL Nieuws — „kospi zuid-korea”
- FD — „kospi zuid-korea”