On Wednesday, South Korea's Kospi index plunged over 5%, closing at 7,246.79 points. Following a sharp decline the previous day, the index has now fallen approximately 23% from its historic high set in June, officially entering technical bear territory. This dramatic volatility signals that the previously highly coveted AI chip trade is facing a severe market test after an extreme rally.
The core driver of this decline is overextended previous gains. The major South Korean index touched a record high of 9,385.59 points in June, with year-to-date gains once exceeding 100% and rising over 130% compared to a year ago. Faced with such astonishing returns, profit-taking pressure inevitably came to a head. Once negative catalysts emerged, capital quickly shifted from chasing gains to realizing profits. This sell-off was not due to a single factor but resulted from a combination of declining heavyweight stocks, weakness in the US semiconductor sector, overheated retail leverage, and foreign capital outflows.
The current structural risk in the South Korean stock market lies in its excessive reliance on a few semiconductor leaders. Samsung Electronics and SK Hynix together account for about half of the Kospi's weighting. On Wednesday, both fell 6.3% and 5.7% respectively, directly dragging down the entire index. This high concentration means the market benefits from the AI boom but is also more vulnerable to sharp pullbacks when sentiment reverses. This is not a standard broad market correction but rather a concentrated deleveraging of crowded AI chip trades.
Regarding capital flows, international investors have been net sellers for most of this year, while local retail investors were the key force driving the previous index surge. Many retail participants entered the market via margin trading or leveraged ETFs, amplifying volatility. Regulators had previously expressed concern over excessive retail leverage. When the market turned, margin calls and risk control measures accelerated the decline. Market analysts note that leveraged products tied to heavyweight stocks further exacerbated the volatility.
Skepticism regarding the AI chip cycle is also growing. Investors are concerned about whether AI-related capital expenditure is overheated and if memory chip demand can sustain high-speed growth. News regarding Chinese AI platforms planning to develop proprietary chips, along with increased attention on Chinese semiconductor enterprises, has deepened investor concerns about long-term competition and supply chain substitution risks. Meanwhile, the downturn in the US semiconductor sector has further dampened sentiment for South Korea's AI semiconductor segment.
In the short term, SK Hynix's upcoming plan to list American Depositary Receipts (ADRs) in the US also creates pressure on capital flows. While beneficial for expanding the investor base in the long run, the short-term supply of new equity may absorb market funds and trigger profit-taking. The market will now focus on the performance of these ADRs and the second-quarter earnings reports scheduled for release by the two semiconductor leaders at the end of July.
With the index falling significantly, valuations in the South Korean stock market are rapidly becoming more attractive. Data shows the Kospi currently has a forward 12-month P/E ratio of about 7.6x, clearly lower than the overall emerging market level and far below the S&P 500. However, this does not mean risks have vanished. The core of short-term trading depends on whether the earnings cycle, capital flows, and AI trade sentiment can stabilize. If earnings and guidance prove strong AI memory demand, market sentiment may recover. However, if foreign capital continues to flow out or global investors question the sustainability of AI capex, low valuations may temporarily fail to prevent continued market volatility.
