Kospi surges over 3% at open as US tech stocks rebound; Samsung Electronics, SK hynix lead gains

The Kospi surged more than 3 percent in early trading Wednesday, lifted by an overnight rebound in AI and semiconductor stocks on Wall Street.

Large-cap chipmakers Samsung Electronics and SK hynix led the advance, briefly pushing the benchmark index above the 5,800 mark before gains began to moderate.

According to Korea Exchange, the Kospi opened up 137.34 points, or 2.43 percent, at 5,786.13 and has since been trimming its advance.

Foreign and institutional investors are driving the rally. In the Kospi market, foreigners and institutions are posting net purchases of 91.9 billion won ($68.5 million) and 12.1 billion won, respectively, while retail investors are net selling 117.3 billion won.

The broad-based gains reflect the spillover from Wall Street's tech rebound, which sent domestic chip heavyweights sharply higher.

On the New York Stock Exchange, Micron rose 2.58 percent, SK hynix's American depositary receipts gained 2.09 percent, and SanDisk climbed 4.78 percent, helping lift the Nasdaq Composite by 0.83 percent and the Philadelphia Semiconductor Index by 2.63 percent.

AMD was a particular catalyst: the company posted record quarterly earnings on surging AI data center chip demand in the third quarter and issued fourth-quarter guidance that topped market expectations, sending its shares sharply higher both during regular trading and in after-hours sessions — a positive signal for domestic markets.

Apple's warning during its fiscal fourth-quarter earnings call — covering the July-to-September period — that memory chip prices could keep rising into next year also helped ease market concerns about the semiconductor industry outlook. Bargain buying after several consecutive sessions of declines was an additional factor.

Samsung Electronics and SK hynix are up 3.19 percent and 5.15 percent, respectively. SK Square is gaining 6.34 percent, Samsung Electro-Mechanics 4.98 percent, and Hyundai Motor 0.90 percent. LG Energy Solution is down 2.07 percent and Samsung Biologics is off 1.72 percent.

The Kosdaq is also advancing, opening up 11.35 points, or 1.61 percent, at 715.74. In that market, retail investors are net buying 66.7 billion won, while foreigners and institutions are net selling 30.7 billion won and 20.7 billion won, respectively.

Among top Kosdaq stocks by market cap, Ecopro is up 2.85 percent, Ecopro BM 2.05 percent, and Jusung Engineering 3.55 percent. Alteogen is down 3.75 percent, HLB is falling 17.44 percent, and Hugel is off 0.37 percent.