KOSPI surges past 7,800 as Samsung, SK Hynix lead chip rally
Synopsis
South Korea's KOSPI has hit a fresh record above 7,800 for a fifth straight session, with Samsung Electronics and SK Hynix leading a chip-driven surge that pushed the combined KOSPI-KOSDAQ market cap past 7,000 trillion won for the first time ever — even as US-Iran peace talks showed signs of unravelling.
Key Takeaways
KOSPI surged 324.22 points or 4.32% to 7,822.22 on 11 May , hitting a fresh record for the fifth consecutive session .
The index briefly touched 7,876.60 intraday, with the 8,000-point milestone now in sight.
Combined KOSPI and KOSDAQ market capitalisation surpassed 7,000 trillion won (US$4.75 trillion) for the first time in history.
Samsung Electronics gained 6.33% and SK Hynix skyrocketed 11.68% , both reaching new highs.
A buy-side sidecar was triggered at 9:29 am , halting programme trading for five minutes due to the sharp rise.
US President Trump's rejection of Iran's peace offer added geopolitical uncertainty but failed to dampen the rally.
South Korea's benchmark Korea Composite Stock Price Index (KOSPI) surged to a fresh record high of 7,822.22 on Monday, 11 May, climbing 324.22 points or 4.32% as of 11:20 am local time, driven by a powerful rally in blue-chip semiconductor stocks. The index briefly touched an intraday peak of 7,876.60, extending its record-breaking run into a fifth consecutive session and placing the unprecedented 8,000-point milestone within striking distance.
Historic Market Capitalisation Milestone
Monday's surge pushed the combined market capitalisation of the KOSPI and the secondary bourse KOSDAQ past 7,000 trillion won (approximately US$4.75 trillion) for the first time in history. To put the pace of this rally in context, the combined market cap crossed 4,000 trillion won on 2 January and breached 6,000 trillion won on 27 April — a near doubling in just over four months.
Circuit Breaker Triggered Amid Sharp Gains
The velocity of Monday's rise was sharp enough to trigger a buy-side sidecar at approximately 9:29 am, halting programme trading for five minutes. Such measures are designed to cool runaway momentum and are rarely activated, underscoring the unusual intensity of the session's opening move.
Chip Stocks Drive the Rally
Major chipmakers were the primary engine of Monday's gains, tracking a strong close on Wall Street the previous Friday. In the US, Micron soared 15.49%, AMD jumped 11.44%, and Nvidia rose 1.75%, fuelled by enthusiasm around chip and artificial intelligence (AI) spending.
In Seoul, market heavyweight Samsung Electronics surged 6.33% to a new high, while chipmaking rival SK Hynix skyrocketed 11.68%, also hitting a fresh record. AI investment firm SK Square advanced 5.1%, and trading conglomerate Samsung C&T climbed 5.21%.
Broader Market Moves
Auto stocks also participated in the rally. Hyundai Motor rose 2.45%, while affiliate Kia added 5.47% and auto-parts maker Hyundai Mobis escalated 7.66%. Major shipbuilder HD Hyundai Heavy gained 3.04%. Battery makers were mixed — LG Energy Solution lost 1.26% while Samsung SDI edged up 1.33%. Electrical shares lost ground, with HD Hyundai Electric down 2.71% and LS Electric dropping 3.83%. The Korean won was trading at 1,472.7 won per US dollar as of 11:20 am, marginally weaker by 1.0 won from the previous session.
US-Iran Uncertainty Fails to Dent Sentiment
Monday's gains came despite a fresh geopolitical headwind: US President Donald Trump stated earlier in the day that he cannot accept Iran's peace offer, raising concerns about a potentially collapsed US-Iran peace deal. That uncertainty, however, did little to dampen investor appetite in Seoul, where the chip-driven momentum proved dominant. With the KOSPI now firmly above 7,800 and the 8,000-point threshold in sight, all eyes will be on whether global chip demand signals and US-Iran developments can sustain — or disrupt — the rally's trajectory.
Point of View
However, is the combined KOSPI-KOSDAQ market cap crossing 7,000 trillion won: that milestone, achieved in barely four months from 4,000 trillion won, reflects a liquidity-driven re-rating that fundamentals will eventually need to justify. The US-Iran breakdown, brushed aside on Monday, remains a live risk — and any oil-price spike or risk-off contagion could test how much of this rally is conviction versus momentum.
NationPress
12 May 2026
Frequently Asked Questions
Why did the KOSPI surge above 7,800 on 11 May?
The KOSPI surged 324.22 points to 7,822.22 on 11 May, driven primarily by a sharp rally in semiconductor stocks including Samsung Electronics and SK Hynix, which tracked strong gains by US chip companies like Micron and AMD on Wall Street the previous Friday.
What is the significance of the 7,000 trillion won market cap milestone?
The combined market capitalisation of the KOSPI and KOSDAQ crossing 7,000 trillion won (approximately US$4.75 trillion) on 11 May marks a first in South Korean financial history. The figure had stood at 4,000 trillion won as recently as 2 January, making the near-doubling in four months a remarkable pace of re-rating.
What is a buy-side sidecar and why was it triggered?
A buy-side sidecar is a circuit-breaker mechanism that halts programme trading for five minutes when the market rises too sharply in a short window. It was triggered at approximately 9:29 am on Monday due to the velocity of the KOSPI's opening gains, a rare occurrence that signals unusually intense buying momentum.
How did US-Iran tensions affect South Korean markets?
US President Donald Trump's statement that he cannot accept Iran's peace offer raised concerns about a collapsed peace deal, adding geopolitical uncertainty. However, the news had little visible impact on Seoul's markets on Monday, with chip-driven sentiment overriding those concerns.
Which South Korean stocks gained the most on 11 May?
SK Hynix led with an 11.68% surge, followed by Samsung Electronics at 6.33%, Hyundai Mobis at 7.66%, and Kia at 5.47%. Samsung C&T and SK Square also posted gains of over 5%, while battery and electrical stocks were mixed or lower.
