South Korean stocks jump 5% as hynix stock leads AI rebound
South Korea's KOSPI jumped more than 5% on Friday, July 3, 2026, as bargain hunters piled back into semiconductor heavyweights after Thursday's near-8% plunge. SK hynix stock led the rebound, soaring over 10% and helping the index reclaim the 8,000 level in a volatile week shaped by swings in AI sentiment. The turnaround capped one of the wildest weeks in global chip markets, with Seoul once again serving as a high-beta barometer for artificial intelligence demand.
Key Takeaways
- The KOSPI climbed about 5.2% to roughly 8,043 on Friday, triggering a buy-side circuit breaker after reclaiming 8,000.
- SK hynix stock surged more than 10% and Samsung Electronics gained over 8%, reversing steep Thursday losses.
- Thursday's 7.9% drop followed AI capacity fears tied to reports that Meta may sell excess computing infrastructure.
- Institutional investors bought a net 2.7 trillion won Friday while foreign and retail traders were net sellers.
- Reports that Anthropic is in talks with Samsung on a custom AI chip added a fresh catalyst for chip buyers.
Why did South Korean stocks jump 5% on Friday?
Investors scooped up discounted semiconductor shares after the previous session's sharp sell-off, according to Bloomberg and Yonhap reports syndicated via TradingView. The benchmark Korea Composite Stock Price Index opened 1.2% higher and extended gains through the session.
By early afternoon local time, the KOSPI traded near 8,043.45, up 395.3 points or 5.17%. The rally was strong enough for the Korea Exchange to implement a buy-side circuit breaker, briefly pausing momentum after gains exceeded 5%.
What triggered Thursday's AI-driven selloff?
The turbulence began on Thursday, when the KOSPI plunged 7.89% to close at 7,648.09. Heavy selling hit Samsung Electronics and SK hynix after media reports that Meta Platforms was exploring ways to monetize excess AI computing capacity, raising fears that Big Tech had overbuilt data-center infrastructure.
An overnight slump in U.S. semiconductor stocks added pressure. The tech-heavy Nasdaq fell 0.8% and the Philadelphia Semiconductor Index dropped 5.4% for a second straight session. SK hynix tumbled 14.57% on Thursday while Samsung lost 9.06%.
How did hynix stock perform during the rebound?
SK hynix was the standout gainer in Friday's turnaround, climbing 10.24% and pulling the broader market higher. Samsung Electronics advanced 8.22%, while Samsung Electronics preferred shares rose 9.70%, according to market data cited in regional reports.
Electric and electronics stocks led sector gains, up 7.34%. Institutional buyers provided the engine: they purchased a net 2.7 trillion won in shares, offsetting 1.4 trillion won in foreign selling and 1.3 trillion won in retail outflows.
What should investors watch next in Korea's AI trade?
Market participants are also tracking reports that AI startup Anthropic is in talks with Samsung Electronics to develop a custom AI chip—a partnership that could reinforce Korea's role at the center of the AI hardware supply chain.
Volatility may persist. Analysts note Korea's benchmark has swung wildly as investors debate whether recent AI spending fears are overblown or early signals of a demand plateau. Upcoming earnings from global chipmakers and Big Tech could determine whether Friday's rebound holds.