Japanese and Korean stocks both plunge on Monday; KOSPI closes down 8.3%
Claire Weston
South Korea's KOSPI plunged 8.29% and the Nikkei 225 fell 3.85% on June 8, with Samsung and SK Hynix dropping as much as 10%; a hotter-than-expected U.S. jobs report flipped rate expectations toward a hike, and a fresh Iran–Israel missile exchange deepened the risk-off mood across Asia-Pacific tech.
How bad was the damage in Tokyo and Seoul?
Korea's KOSPI closed down 8.29% at 7,484.41. Samsung Electronics fell as much as 10% intraday; SK Hynix closed down over 7%. Together the two stocks carry roughly 40% of the index's weight — they alone dragged the benchmark.
The Nikkei 225 closed down 3.85% at 64,024.60. SoftBank fell over 9%, Kioxia over 8%, Tokyo Electron over 5% — Japan's semiconductor supply chain sold off across the board.
This means → when an index's moves are dominated by two or three names, a pullback in those names hits the headline number far harder than the "average stock" experience.
What lit the fuse — what happened in the U.S.?
Last Friday, U.S. May non-farm payrolls came in at 172,000 — well above expectations. Markets began pricing in a possible Fed rate hike this year, not a cut.
The Nasdaq tumbled 4.2%, its biggest one-day drop since April last year. The S&P 500 fell 2.6%, ending a nine-week winning streak.
In plain terms = jobs data too strong → the market decides the Fed may raise, not cut → rate expectations flip → the highest-valued tech stocks get hit first and hardest.
How did the Middle East pour fuel on the fire?
On June 7, Iran launched multiple missile waves at Israel. The outlook for U.S.–Iran talks turned uncertain; crude oil prices rose over 2%.
This means → geopolitical risk stacked on top of rate panic, both forces compressing risk appetite at once and accelerating the exit from high-valuation assets.
What risks were already building inside the Korean market?
Korean equities were among the world's best-performing indices this year, but gains were heavily concentrated in Samsung and SK Hynix — a textbook crowded trade (a handful of stocks absorbing a disproportionate share of capital).
Foreign investors have pulled a record $76 billion from Korean stocks this year. Last week alone, net selling topped $10 billion; the won fell to its weakest against the dollar since March 2009.
Hedge fund Golden Horse Fund Management has trimmed exposure and added derivatives protection. M&G Investments has cut holdings in memory and foundry names, rotating into downstream AI supply-chain plays.
Future Securities analyst Han Ji-young noted that Korean equity-index futures and options expire in concentration this week — combined with won volatility, turbulence could intensify further.
After a drop this steep, did anyone step in to steady confidence?
On the same day, Nvidia CEO Jensen Huang announced a multi-year technology partnership with SK Hynix in Seoul. The two companies will co-develop next-generation AI memory chips and lock in long-term supply commitments.
Huang also plans to meet Samsung Electronics' vice chairman and other Korean business leaders. South Korean President Lee Jae-myung said Korean equities remain undervalued — a remark aimed at calming market sentiment.
If you're an AI company shareholder, you should be happy — and there may be even more opportunity ahead. Right now, it's priced very low.
Jensen Huang
CEO, Nvidia
(June 8, Seoul press event)
Content is for reference only, not financial advice.