SOUTH KOREA · ANALYSIS
Key Facts
- What happened South Korea’s main stock index, the Kospi, jumped 6.63% on 28 October to close at 6,012.44.
- The leaders Samsung Electronics rose 9.01% to 242,000 won (about US$181), and SK hynix rose 10.89%.
- The trigger SK hynix, a leading maker of AI memory chips, reported record third-quarter results and a big shareholder payout.
- What next It was the index’s first close above 6,000 in ten trading sessions; Korea’s October trade data are scheduled for 1 November.
One earnings report turned a nervous stretch in Seoul into a very strong day for the Kospi. SK hynix showed that the AI boom still pays, and chip stocks led the market.
What Moved on Wednesday
The Kospi gained 374.1 points to close at 6,012.44, its first finish above 6,000 in ten trading sessions. The Kosdaq, Korea’s market for smaller and younger companies, rose 3.69% to 771.28.
Futures on the Kospi 200, a basket of the 200 biggest shares, jumped sharply, so the Korea Exchange, which runs the country’s stock market, briefly paused computer-driven buy orders. That safety step, known as a sidecar, is meant to cool a rush.
Foreign investors were net buyers of 815.8 billion won of shares (about US$610 million), and institutions bought 960.8 billion won (about US$718 million). Individual investors sold about 1.8 trillion won (about US$1.35 billion); conversions use about 1,338 won per US dollar.
Why SK Hynix Matters
SK hynix makes high-bandwidth memory, the fast chips that sit next to AI processors in data centres. Its third-quarter results were a record, it announced a shareholder-return programme worth more than 100 trillion won (about US$75 billion) for 2026, and its shares rose 10.89% to 1.487 million won (about US$1,111).
An AI processor can only work as fast as the memory feeding it. That is why makers of high-bandwidth memory, SK hynix among them, sit at the centre of the AI hardware trade, and why its results move the whole sector.
Samsung Electronics, the world’s other big memory maker, gained 9.01% to 242,000 won (about US$181). SK Square, a holding company that owns a stake in SK hynix, climbed 11.23% to 921,000 won (about US$688).
Lee Jae-won, an analyst at Yuanta Securities in Seoul, said the results showed that AI chip demand is turning into profits and shareholder returns. That eased fears that the AI boom had peaked.
In plain English: at about 1,338 won per dollar, US$100 buys roughly 133,800 won, so a 242,000 won Samsung share costs about US$181. Korean stocks are quoted in won, which is why a currency move can change what a US investor earns.
What One Strong Day Does Not Prove
The index had closed below 6,000 for ten sessions before Wednesday. A single rebound does not show that the slump is over, and one day of foreign buying is not yet a trend.
Individual investors were net sellers on the day, so the buying came from foreign and institutional money. When a market leans on a few giants, a disappointment at one of them can move the whole index.
What It Means for You
Samsung Electronics and SK hynix are among the largest companies on the Kospi, so Americans who hold Korea or emerging-market funds feel these swings. The chips also sit inside the AI hardware that US companies buy, which ties Seoul’s results to the wider technology trade.
If your portfolio holds US chip or AI stocks, a Korean memory report is an early read on whether demand is holding up. The won also weakened on the day, so a US investor’s gain in dollars would be smaller than the gain in won.
What to Watch
Korea’s trade data for October are due on 1 November and will show whether chip exports kept growing. The S&P Global manufacturing PMI, a survey of factory managers, is due on 2 November; it stood at 53.9 in September, and a reading above 50 means factories are expanding.
Dates for the trade data and the PMI come from the economic calendar of RT, a market-data provider, and can shift. We will update this article if SK hynix or the exchange publishes further detail.
Frequently Asked Questions
Why did the Kospi jump 6.63% on 28 October 2026?
The Kospi rose after SK hynix reported record third-quarter results and bigger shareholder payouts. Samsung Electronics rose 9.01% and SK hynix 10.89%.
What is the Kospi?
The Kospi is the main stock index of the Korea Exchange in Seoul. It tracks all common shares on the exchange, and chipmakers carry a large weight.
Sources: South Korea’s Korea Exchange closing data, 28 October 2026; SK hynix earnings release; RT, a market-data provider, economic calendar (trade data and PMI dates). Related: Asia, Markets, Egypt and South Korea Launch Trade Talks.
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief
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