South Korean stock market soared more than 3% on Tuesday, with the Composite Stock Price Index (KOSPI) closing up 3.09% at 5,638.34 points, with gains approaching 5% at one point during the session. Externally, it benefited from the boom in U.S. stocks (AI) and the positive stimulus of (Anthropic) submitting (IPO), while internally, it was boosted by South Korea's third-quarter (GDP) data that far exceeded expectations, with these dual positives triggering a rise in chip stocks.

Core Driving Factors

• Strong economic data: South Korea's growth in the third quarter GDP exceeded market expectations, mainly due to the strong boost from the global artificial intelligence boom on South Korea's semiconductor exports and investments.
• Significant inflow of foreign capital: Foreign investors bought a large amount today in the South Korean stock market, exceeding 593 billion Korean won, which is approximately 447 million US dollars.
• US stock linkage effect: Overnight, the Philadelphia Semiconductor Index in the US market soared by over 2%, and the optimistic sentiment towards the AI sector spread across to local tech stocks.

Performance of heavyweight stocks

Leading sectors (Technology and Chips)

• SK Hynix ( SK Hynix ): Soaring 5.18%.
• Samsung Electronics ( Samsung Electronics ): Up 4.23%.
• Batteries and Industrial Giants: POSCO Holdings rises 2.41%, LG New Energy ( LG Energy Solution ) rises 2.00%.
• Automotive sector: Kia Motors and Hyundai Motor rose by 1.33% and 0.87% respectively.

Decline against the trend

• Samsung Biopharmaceuticals ( Samsung Biologics ): Performed weakly, closing down 5.37%.

Market Institution Analysis

Samsung Securities analysts Seo Sang - young pointed out that data GDP that exceeded expectations, continued strong exports, and strong corporate earnings performance are using real, tangible data to dispel previous market concerns about the sustainability of "AI investments," providing strong support for the robust rebound in the stock market.

According to data from the Bank of Korea, if large American technology companies slow down their capital expenditures in the field of artificial intelligence next year, South Korea's semiconductor exports could decrease by $50 billion to $100 billion compared to previous forecasts. In a written response submitted to lawmaker Andoje ( Ahn Do - geol ), the Bank of Korea constructed a "pessimistic scenario" to assess the impact that would be on South Korea's economy if American tech giants cut back on their large-scale infrastructure investments. Under this scenario, a sharp decline in exports would lead to a reduction of about 0.4 percentage points in South Korea's gross domestic product ( GDP ) growth rate next year; at the same time, it would also result in South Korea's current account surplus being significantly lower than the Bank of Korea's previous forecast of a $430 billion surplus for 2027. This scenario assumes that the unit price of South Korean semiconductor products will fall by 10%.