Seoul's KOSPI falls 3.65% and Samsung and SK hynix lose more than 4% as doubts over OpenAI's revenue reach Asian trading
It was the index's biggest one-day fall since 2 September. Taipei's Taiex fell more than 540 points early on chip stocks, then closed almost flat as money moved into optics and shipping stocks. Japan was shut for a holiday.
Why it matters: The reports that OpenAI's revenue was about $20bn below what had been signalled have reached Asian trading, and the two biggest makers of AI memory took some of the hardest hits. How far one lab's numbers can move chip stocks on the other side of the world shows how much of the AI trade rests on a few customers.
South Korea's benchmark KOSPI closed on Monday 12 October at 6,384.24, down 241.69 points or 3.65%, the Korea Times reports. It says that was the index's biggest one-day percentage fall since 2 September, when it lost 3.99%. Samsung Electronics fell 4.39% and SK hynix 4.52%, despite Samsung's record third-quarter earnings guidance last week. The tech-heavy Kosdaq fell 4.83% to 849.19.
The Korea Times ties the sell-off to renewed worries about an AI bubble after reports that OpenAI's annual revenue was $20bn lower than previously reported. It adds that the gap reflected different accounting methods rather than a drop in sales, and that OpenAI-related concerns alone do not fully explain the market's weakness. Yonhap, carried by UPI, gives a different account: a tech sell-off driven by inflation worries and high oil prices, with no mention of OpenAI. It counts 2.02 trillion won of net selling by foreign investors.
In Taipei the Taiex opened lower and fell more than 540 points in early trading, led by large chip stocks, after the Philadelphia Semiconductor Index dropped 3.77% over Thursday and Friday, the Central News Agency reports. Dealers told CNA that drop followed reports that OpenAI's annualised revenue was about US$20bn lower than previously reported. The index then recovered as money moved into co-packaged optics (CPO) and shipping stocks, and it closed down 11.48 points, or 0.02%, at 49,301.96. TSMC fell 0.39% to NT$2,540. Japanese markets were closed for a public holiday.
The revenue reports first appeared in the FT and were followed by Reuters on 8 October. The two accounts of Seoul's fall do not agree on how much of it is about AI, and the Switchboard shows both.
- Reported The KOSPI closed at 6,384.24, down 241.69 points or 3.65%, its biggest daily percentage fall since 2 September; Samsung Electronics fell 4.39% and SK hynix 4.52%, the Korea Times reports. The Korea Times
- Reported The Korea Times links the fall to AI-bubble worries after reports on OpenAI's revenue, and says the $20bn gap reflected different accounting methods rather than a drop in sales. The Korea Times
- Reported Yonhap puts foreign investors' net selling at 2.02 trillion won and blames inflation worries and high oil prices; its report does not mention OpenAI. Yonhap, via UPI
- Reported The Taiex fell more than 540 points early, led by large chip stocks, then closed down 0.02% at 49,301.96 as funds moved into CPO and shipping stocks; TSMC lost 0.39%. Central News Agency (Focus Taiwan)
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