US Stock Market Summary for June 23, 2026

On June 23 (local time), the US stock market plunged on a broad selloff of tech stocks centered on semiconductors. The Nasdaq closed down 2.21% at 25,587 and the S&P500 also fell 1.44%, while the Dow held up comparatively well with a mild 0.09% dip. A wave of global semiconductor selling that began with a slump in Korea's KOSPI spread into the US, sending Micron and Sandisk down more than 13%, while concerns over debt-funded AI capital expenditure froth combined with the Fed's hawkish stance (90% probability of a hike this year). Money moved decisively into defensives — healthcare, consumer staples and telecom — while the volatility index (VIX) spiked 19% to 19.5, underscoring a sharp rise in market caution.

Winners and losers diverged sharply by sector. Tech ($XLK) led the decline with a 4.14% plunge, while cyclically sensitive areas such as industrials (-2.01%), materials (-1.45%) and discretionary (-1.03%) also posted losses. By contrast, defensive sectors broadly advanced: consumer staples ($XLP +1.87%) led the pack, followed by real estate, healthcare (+1.41%), utilities (+0.78%), energy (+0.74%) and even telecom and financials — a textbook risk-off rotation.

Bonds edged higher on safe-haven demand (long-dated $TLT +0.15%), although rate-hike jitters capped gains. In commodities, silver ($SLV) fell 5.4% on a strong dollar and risk-off mood, with uranium (URA) down 2.61%, gold ($GLD) 1.89% and crude ($USO) also dropping 1.27% on easing US-Iran tensions, leaving the complex broadly weaker.

Decliners were concentrated in semiconductors. Sandisk ($SNDK) plunged 13.75% and Micron ($MU) fell 13.18%, with ARM ($ARM) -10.14%, Marvell ($MRVL) -9.36%, Lam Research ($LRCX) -9.33% and KLA ($KLAC) -9.17% all tumbling — a wipeout across memory and equipment names. Reports that Korea's SK Hynix would temper the pace of its AI memory capacity expansion and a Bank of America note warning on rate hikes triggered the move (source).

Meanwhile, the funds flowed to economic defensives. IBM ($IBM) rose 5.04%, Merck ($MRK) 3.57%, Johnson & Johnson ($JNJ) 3.37%, Novo Nordisk ($NVO) 3.36%, AT&T ($T) 3.21% and Philip Morris ($PM) 3.19%, with pharma, telecom and tobacco all posting gains. The pattern of capital leaving tech and rotating into names with stable cash flows was unmistakable (source).

> Key events for the next trading session will be displayed automatically.

> "Recent AI-related developments are raising questions about the enormous capital expenditures going into semiconductor equipment investment and capacity expansion."

> — Thomas Martin, Senior Portfolio Manager, Globaltr

> "Today's tech rout, without any specific catalyst, is another instance of expanding volatility created by earnings expectations and valuations that increasingly look bubble-like."

> — James Riley, Senior Market Economist, Capitaleconomics

> "I don't think the AI tech-stock adjustment is over yet. Positioning was extremely one-sided, and leveraged products and bullish sentiment had become excessive."

> — Adam Turnquist, Chief Technical Strategist, LPL Financial

Today's signals — with semiconductors and software simultaneously oversold and financials and pharma overbought — clearly point to a risk-off rotation. However, trend indicators on some semiconductor names should be read with caution, as they are lagging signals reflecting data captured before the plunge. Near-term inflection points are Wednesday's Micron earnings and Thursday's PCE price index. View the technical signals report