US 30-year Treasury yields at a 19-year high triggered a global equity selloff, with South Korea's KOSPI falling 6% and triggering a circuit breaker.
US 30-year Treasury yields at a 19-year high triggered a global equity selloff, with South Korea's KOSPI falling 6% and triggering a circuit breaker.

Global equities fell 2% as 30-year US Treasury yields hit a 19-year high, triggering a KOSPI circuit breaker and a 3% Nikkei slide.
"Nothing kills momentum like rising rates, and today proved that point," said Tony Welch, chief investment officer at SignatureFD.
The MSCI Asia Pacific Index dropped 2%, its largest single-day decline since July 29. South Korea's KOSPI opened at 6,528.77, down 4.96%, before sliding to 6,404.26 — a 6.78% decline that triggered the exchange's circuit breaker mechanism. Japan's Nikkei 225 briefly broke below 66,000, testing 65,412, a drop of 2,048 points or 3.03%. The Philadelphia Semiconductor Index had plunged 4.98% on Tuesday to 11,992.463, with memory names bearing the brunt.
The selloff reflects a convergence of pressures: surging long-dated yields eroding equity valuations, elevated oil prices from Middle East tensions, and profit-taking in the semiconductor complex after a 20% rally. Investors rotated into healthcare (+1.6%) and consumer staples (+1.1%) within the S&P 500, while the VIX rose 0.65 points to 15.84, its highest close since Aug. 4. The next test comes with Nvidia's earnings report, which will determine whether AI hardware demand can justify current valuations.
The 30-year US Treasury yield briefly spiked to a 19-year high during Tuesday's session, reflecting concerns over the US fiscal deficit, government debt expansion, and persistent inflation. The 10-year yield declined more than 1 basis point to 4.706%, while the 2-year yield slipped less than 1 basis point to 4.175%. Japan's 10-year government bond yield hit a fresh 30-year high, Germany's 30-year bund yield climbed to its highest level since 2011, and France's 30-year yield touched its highest point since 2008.
US stocks closed lower for a third consecutive session on Tuesday, with the Dow Jones Industrial Average falling 116.38 points to 53,343.4, a decline of 0.22%. The S&P 500 dropped 0.69% to 7,691.76, while the Nasdaq Composite tumbled 1.33% to 26,289.71. The Russell 2000 fell approximately 1.3%, with small-cap stocks under similar pressure. Among mega-cap tech, Meta fell 4.45%, Nvidia dropped 2.34%, and Tesla declined 0.72%, while Apple rose more than 1% and Microsoft edged up 0.27%.
The Philadelphia Semiconductor Index plunged nearly 5% on Tuesday, with memory and storage names suffering the heaviest losses. South Korea's SK Hynix, Seagate Technology, and SanDisk all fell more than 9%, while Micron Technology and Western Digital dropped over 7%. ARM and Intel declined more than 6%, while AMD, ASML, and TSMC fell over 4%. Optical communications stocks also tumbled, with Coherent plunging 12.84% and Lumentum falling over 9%. TSMC's ADR fell $17.47, or 4.05%, to close at $413.50.
The selloff extended into Asian trading on Wednesday. SK Hynix fell more than 8% and Samsung Electronics dropped over 7% in Seoul, while Kioxia plunged 9% in Tokyo. Taiwan's stock market faced additional technical pressure as index futures settled, with market participants bracing for amplified selling.
US President Donald Trump stated on social media that there are no talks with Iran and there will be none in the future, emphasizing that the US naval blockade remains fully effective. White House officials have reportedly shifted Iran strategy from "striking Iran hard as quickly as possible" toward a longer-term approach of "choking Iran." International oil prices remained elevated, with WTI crude rising 44 cents to $84.94 per barrel and Brent crude gaining 15 cents to $91.02 per barrel. Spot gold fell nearly 1.9% to $4,331.77 per ounce, while spot silver dropped 3.74% to $63.315 per ounce.
This article is for informational purposes only and does not constitute investment advice.