(LEAD) Seoul shares close at new high on tech rally amid AI optimism

Lead

South Korean stocks closed at a fresh record high above the 8,800-point level on Tuesday, as technology shares continued to advance on optimism over artificial intelligence (AI), led by chip giant Samsung Electronics, offsetting a market-wide profit-taking mode.

The benchmark Korea Composite Stock Price Index (KOSPI) added 13.11 points, or 0.15 percent, to close at 8,801.49, according to Yonhap News Agency. The index opened higher and climbed to a record intraday high of 8,933.62 before reversing course and falling nearly 3 percent at one point amid profit-taking. It later recouped part of its losses but ended the session slightly higher.

The local currency fell sharply against the U.S. dollar, Yonhap reported.

Coverage Comparison

The latest advance extends a remarkable run for South Korean stocks, which have repeatedly set new records in recent days. On Monday, the KOSPI added 311.85 points, or 3.68 percent, to close at a then-record 8,788.38, according to Yonhap. That session saw the index open at a record high and extend its gains, prompting the Korea Exchange to activate a buy-side sidecar, which suspended program trading of KOSPI stocks for five minutes.

The Monday rally was driven by strong gains in stocks related to AI, including major chipmakers, Yonhap reported. Trade volume was heavy at 618.17 million shares worth 69.4 trillion won (US$46.1 billion), with losers outnumbering winners 712 to 194. Institutions and individuals scooped up a net 2.53 trillion won and 377.31 billion won, respectively, while foreigners unloaded a net 2.91 trillion won.

Just a week earlier, on May 27, South Korean stocks had risen for the fourth consecutive session to a new peak above the 8,200-point mark, driven by a strong rally by Samsung Electronics and SK hynix. The KOSPI gained 181.19 points, or 2.25 percent, to close at a record 8,288.7, after rising as high as 8,457.09. The index opened 2.42 percent higher and extended gains, with a buy-side sidecar issued to halt KOSPI futures for five minutes. Trade volume was heavy at 615.2 million shares worth 55.8 trillion won (US$37.2 billion), with losers far outnumbering winners 75 to 823. Individuals purchased a net 403.4 billion won worth of shares and institutions bought a net 189.6 billion won, offsetting net foreign selling of 448.4 billion won. Foreigners remained net sellers for the 15th consecutive session.

The rally in Seoul mirrors a broader AI-driven surge across Asia. Japan's stock market has hit an all-time high as a global buying frenzy driven by AI shows no signs of slowing down, Al Jazeera reported. The Nikkei 225 rose nearly 3 percent on Wednesday, lifting the benchmark index above 68,000 for the first time. Japanese firms involved in the semiconductor business led the gains, with Tokyo Electron, Japan's largest manufacturer of semiconductor equipment, soaring as much as 14 percent in morning trading. Advantest, a supplier of testing equipment to the semiconductor industry, rose more than 5.5 percent, and Shin-Etsu Chemical, a supplier of silicon wafers, gained about 4 percent.

Key Claims

• The KOSPI closed at 8,801.49 on Tuesday, a fresh record high, after adding 13.11 points, or 0.15 percent, according to Yonhap.
• The index hit a record intraday high of 8,933.62 before falling nearly 3 percent amid profit-taking, Yonhap reported.
• The local currency fell sharply against the U.S. dollar on Tuesday, according to Yonhap.
• On Monday, the KOSPI added 311.85 points, or 3.68 percent, to close at 8,788.38, a record at the time, Yonhap reported. The index hit a new intraday high of 8,874.16.
• On May 27, the KOSPI gained 181.19 points, or 2.25 percent, to close at a record 8,288.7, after rising as high as 8,457.09, Yonhap reported.
• The number of South Koreans who own stocks surged from about 6 million in 2019 to more than 14.5 million at the end of 2025, according to the Korea Securities Depository, as reported by Al Jazeera.
• The AI-driven demand for memory chips has delivered Samsung Electronics and SK Hynix record-shattering profits, Al Jazeera reported.
• Japan's Nikkei 225 rose nearly 3 percent to close above 68,000 for the first time, Al Jazeera reported.
• South Korea's exports surged 53 percent from a year earlier to a new monthly high of US$87.8 billion in May, driven by the semiconductor supercycle, government data showed, as reported by Yonhap.

Perspectives

The AI-driven rally has drawn in a broad swath of South Korean society. Al Jazeera reported on the example of Kim Ha-young, a Seoul office worker in her 30s who bought shares in SK Hynix and Samsung Electronics for the first time last year. She told Al Jazeera that her stakes in both companies have more than doubled in value since February. The number of South Koreans who own stocks has surged from about 6 million in 2019 to more than 14.5 million at the end of 2025, according to the Korea Securities Depository, as reported by Al Jazeera.

Market analysts have pointed to the AI-driven semiconductor boom as the key driver of the rally. "The two biggest semiconductor shares led the rally," Kim Seok-hwan, an analyst at Mirae Asset Securities, told Yonhap, noting that other semiconductor-related shares fell on profit taking. Lee Kyung-min, an analyst at Daishin Securities, told Yonhap that the local stock market experienced heightened volatility as investors locked in profits following the recent sharp rally, with continued foreign selling weighing on share prices.

At the same time, there are broader economic concerns. Al Jazeera reported that South Korea's economy faces the prospect of weak long-term growth amid a rapidly ageing labour force, even as the AI-driven demand for memory chips has delivered record-shattering profits to Samsung Electronics and SK Hynix.