Heart-stopping meltdown! South Korea's "AI bull market" faces the ultimate test: KOSPI index plunges, dropping by a staggering 4.7%. The "chip boom" triggers expectations of interest rate hikes.

The South Korean Composite Stock Price Index (KOSPI) plummeted by 4.7% after opening on Monday, with a total decline of over 10% in two days. In just seven trading days, the "world's hottest stock market" has fallen from 8000 points to face an unprecedented stress test. Subsequently, buying funds re-entered the market, leading to the index recovering from its early losses and recording a moderate increase. Meanwhile, the yield of the South Korean 3-year government bonds surged by over 86 basis points from its low this year, reaching the highest level since November 2023 - the bond market sell-off was equally brutal. The fleeting appearance of the 8000 point mark: Vulnerability brought by the concentration of technology stocks. Shortly after the opening of KOSPI on Monday, there was a brief 4.7% plunge, expanding the cumulative decline from the high point on May 14 (8114 points) to over 10%, briefly entering a technical pullback territory. After a sharp drop in stock index futures, the Korea Exchange temporarily triggered a circuit breaker for KOSPI, halting program trading for 5 minutes. This plunge followed last Friday's black trading day, during which the KOSPI index briefly surpassed the unprecedented high point of 8000 points before plummeting, dropping by over 7% at one point during the day. According to exchange data, overseas investors net sold approximately 44 trillion Korean won (about 29.4 billion US dollars) on the KOSPI index, in addition to the approximately 27 trillion Korean won sold off in the previous seven trading days, foreign funds have cashed out over 56 trillion Korean won in the past two weeks. The technology sector bore the brunt, with a net outflow of funds exceeding $2.5 billion for the week; the iShares MSCI South Korea ETF listed in the US has seen continuous outflows for the past three weeks, shrinking assets by over $1.2 billion. The Chief Investment Officer of Eugene Asset Management stated that after a significant increase in the index over the past month, this decline is a "natural pullback," with rising yields and the Samsung strike event triggering the drop. However, this is not the start of a structural decline, but rather a "healthy correction," providing another opportunity to buy quality stocks. Nevertheless, several analysts have warned that given the upward momentum of the KOSPI index and its highly concentrated structure, it is difficult for the KOSPI to sustain its current upward trend in the long term. The index's Price-to-Earnings ratio has risen to around 30 times, much higher than the S&P 500 index's around 22 times, making it one of the most highly valued major indices globally. Technical indicators also show that the index has been extremely overbought for the past few months - reaching this level for the first time in years; historically, assets that are highly overbought often experience significant pullbacks. The highly concentrated structure of the KOSPI makes it more fragile. The combined market value of Samsung Electronics and SK Hynix, the two major memory chip giants, accounts for nearly 40% of the total market capitalization of the KOSPI. Boosted by demand for AI-driven chips, Samsung Electronics' stock price surged by over 180% from the beginning of the year to the high point on May 14, with the total market value surpassing the trillion-dollar mark; SK Hynix was also approaching this milestone. However, the structure of this "dual-engine" driven surge magnifies market volatility - when investors collectively take profit, the simultaneous decline of these two heavyweight stocks is enough to drag the entire index into the circuit breaker zone. Samsung labor-management conflicts ignite supply chain anxieties Amidst a historic high in the semiconductor industry's prosperity, a labor-management dispute that could have significant economic consequences is nearing a tipping point. The Samsung Electronics union has announced a comprehensive strike starting on May 21, lasting for 18 days, with over 40,000 employees registered to participate. This is the largest strike threat in the history of Samsung Electronics and the company's first comprehensive labor standoff in over half a century. The core conflict of this strike lies in profit distribution. In the first quarter of 2026, Samsung Electronics achieved a record-high quarterly profit: an operating profit of 57.2 trillion Korean won, a 756% year-on-year increase, with the semiconductor business contributing 53.7 trillion Korean won to the profit, compared to just 1.1 trillion Korean won in the same period last year, a year-on-year increase of over 48 times. Against the backdrop of nearly a 50-fold year-on-year surge in profit for the semiconductor sector, the union is demanding the company allocate 15% of its operating profit for employee performance bonuses, while Samsung has agreed to a 10% proposal. As a reference, the competitor SK Hynix has agreed to set aside 10% of the company's annual operating profit as a performance bonus pool in full and has abolished the previous bonus cap limit. Under the current distribution system of the two companies, under the same conditions, the bonuses for SK Hynix employees can be more than three times that of Samsung employees. Samsung Electronics Chairman Lee Jae-yong returned from an overseas business trip on May 16 and made a public apology at Incheon International Airport, calling for solidarity between the union and the company. He stated, "Now is the time for us to come together and move in the same direction," and promised to take full responsibility. However, negotiations between the labor and management sides of Samsung Electronics that began in December 2025 broke down in March 2026, and a marathon negotiation from May 11 to 13 failed to narrow the differences on performance bonus payment standards. South Korean President Lee Jae-myung stated via social media on May 18, "Workers should receive fair wages for their labor, and shareholders who take risks and invest also have the right to share in corporate profits." He cited the idiom "too much of anything is bad" to emphasize that anything taken to an extreme could have side effects. The government is currently considering initiating emergency adjustment powers - once activated, relevant companies must immediately cease all labor disputes including strikes, and no strike action can be taken within 30 days. If this strike breaks out in full force, it could not only result in losses exceeding over 40 trillion Korean won (about 182.4 billion RMB) for Samsung itself, but also impact the global semiconductor supply chain. Samsung Electronics holds around 40% of the global memory chip market and plays an irreplaceable role in key components such as High-Bandwidth Memory (HBM) for AI computing power. At a time when the AI investment boom is driving global semiconductor demand to historic highs, any interruption in Samsung's production line could trigger a chain reaction in the global tech supply chain. "From finding a new oil field to diagnosing overheating": Amidst the AI investment boom, rate hike expectations reshape the South Korean yield curve More alarming than the stock market is the structural shift in the South Korean bond market. The yield of the most sensitive 3-year South Korean government bonds rose to 3.77% last week, the highest level since November 2023. Traders in the Korean won interest rate swap market have priced in expectations of the Bank of Korea tightening monetary policy by nearly 120 basis points over the next year. The yield spread between 3-year government bonds and the benchmark rate (2.5%) has widened to over 120 basis points, the largest gap since the rate hike cycle after the 2022 pandemic. This sharp rise in rates is not an isolated phenomenon, but a significant part of the global bond sell-off trend. The yield on the US 2-year Treasury bond rose to 4.06%, hitting a new high since March 2025; the yield on the US 10-year Treasury bond rose to 4.530%, the highest since May 2025; and the yield on the US 30-year Treasury bond surpassed 5.071%, the highest since July 2025. The interest rate on the 20-year Japanese government bond rose to 3.61%, the highest since 1996. The 3-year South Korean government bond yield is moving in tandem with global rates, but its rising amplitude and speed are particularly pronounced in Asian markets. An analyst at iM Securities fixed income stated, "The market increasingly believes that South Korea's economic growth next year may exceed the mid-2% range, while the Bank of Korea's previous forecast was 1.8%." She added that such growth poses significant risks to the bond market. Citigroup currently projects that the Bank of Korea will raise interest rates four times over the next year, by 25 basis points each time, compared to the previous expectation of only two hikes. Cho Yong-gu, a fixed income analyst at Shinyoung Securities, warned, "It is too early to assert that bond yields have peaked. Rising oil prices, strong economic growth, and additional fiscal spending from tax incentives all have negative impacts on the bond market." The central driving force behind the recent turmoil in the South Korean market is not the traditional "hot money departure" or "external shock," but the systematic overheating brought about by the semiconductor and AI investment cycles. Barclays economist Bumki Son wrote in a report, "The exponential growth in AI investment spending is generating an innovative shock to South Korea's nominal and real exports." He likened the boost from the semiconductor and AI boom to "discovering new oil reserves." South Korea's actual GDP growth in the first quarter was 1.7%, far exceeding market expectations of 0.9%. Major investment banks globally have collectively raised their forecasts for South Korea's 2026 economic growth: JPMorgan has raised its forecast from 2.2% to 3.0%, Citigroup to 2.9%, Goldman Sachs to 2.5%, and Barclays and Nomura Securities have also slightly raised their forecasts. Simultaneously, with the backdrop of rising energy prices due to the Middle East situation, South Korea's inflation expectations have also risen - with the average predicted annual consumer price index inflation increasing from 2.4% to 2.5%. The strong semiconductor sales further positively impact government finances. Citibank estimates that South Korea will see an additional revenue of around 20 trillion Korean won (about $13.5 billion) in the second half of 2026, and a further 120 trillion Korean won in 2027. This will support larger-scale government spending, further boosting economic growth expectations and setting higher lower limits on bond yields. While some strategists - including Irene Choi from Goldman Sachs - believe that market pricing for more than four rate hikes is excessive, and expect rates to stabilize if geopolitical tensions ease, analysts point out that the semiconductor industry's boom cycle and the continued expansion of AI investment are fundamentally reshaping South Korea's economic growth trajectory. Conclusion South Korean asset prices are undergoing a structural reshaping triggered by their "own success": the AI-driven semiconductor boom has led to record corporate profits, but has also brought about inflationary pressures, wage demands, and financial overheating - factors that are precisely driving the central bank to shift from "watchful waiting" to "rate hikes." While Citigroup has raised its forecast for South Korea's GDP growth in 2026 to 3%, the market is pricing in nearly 120 basis points of rate hikes in the interest rate swap market. These seemingly contradictory pricing processes are two sides of the same coin. The potential strike of 40,000 Samsung employees is a thread running through the entire situation - a focal point of the concentrated outbreak of distribution disparities in the semiconductor boom, and a key variable to test whether South Korea's economy can operate smoothly in an "overheated" state. The strike deadline this Wednesday (May 21) and the Bank of Korea meeting next Wednesday (May 28) are separated by just seven trading days. In this brief yet crucial time window, an answer to the question of whether "prosperity can be sustained" is about to emerge from the dramatic fluctuations in asset prices.