South Korea KOSPI Crashes 7.2% as Samsung and SK Hynix Break the Market’s Back

South Korea’s Chip Rally Just Unwound

The South Korean stock market was hit hard on Tuesday, with the KOSPI falling 7.2% in its biggest single-day drop since 2024.

What made the reversal feel even more dramatic is that this came after a very strong run. The index had gained 34% since the start of 2025 and had staged a sharp recovery from its April lows, so this was a real shock to sentiment.

A big part of the problem is concentration. The KOSPI’s gains have been heavily driven by just two stocks, Samsung and SK Hynix, so when both of those names sold off hard, the broader index felt it immediately.

Samsung dropped 10% after reports suggested mass production at its U.S. manufacturing facility in Texas may be delayed until 2027. That kind of delay matters. When a major production and capital investment milestone gets pushed back, investors start questioning timing, execution, and near-term growth.

SK Hynix was hit even harder, falling 11.5%, which shows just how quickly confidence can unwind when markets start reassessing semiconductor expectations.

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KOSPI Gets Hit Hardest When Energy Prices Spike

And once that pressure started, it did not stay contained to Korea. The selloff quickly spread across the broader semiconductor trade in the U.S.

Nvidia fell 3%, AMD dropped 4%, Intel lost 4.66%, Micron slid 6.6%, Broadcom was down 3%, and Qualcomm fell 2%.

The weakness also hit specialty chip and equipment names. TSMC dropped 5.1%, Marvell fell 3.5%, and GlobalFoundries lost 5%.

At the same time, rising oil prices added another layer of pressure. Brent crude jumped 7% to $83.04 per barrel as tensions in the Middle East escalated around the U.S.-Israel-Iran conflict.

That matters because higher energy prices immediately raise inflation concerns, and when inflation risk starts climbing, markets tend to get more volatile and far less forgiving.

When we step back, this was not just a bad day for Korean equities. It was a reminder of how quickly concentrated leadership can reverse, and how fast global risk sentiment can crack when semiconductors and energy both move against the market at once.