The AI Trade Imploded in a Day: Nasdaq Down 5.5%, Chip Index Down 12%

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What happened on Thursday

Thursday, November 5, 2026 was the worst day for US tech stocks in 19 months. The Nasdaq Composite fell 5.52% to 24,315, its biggest one-day drop since April 2025, closing in correction territory — 11.9% below its October 6 record close of 27,599.89. The S&P 500 fell 4.36% to 7,353.73 and the Dow dropped 3.44%, shedding 1,833 points to 51,523.06. All eleven S&P 500 sectors ended the day down, with technology off 7.3%.

The damage was concentrated exactly where the excitement had been loudest. The Philadelphia Semiconductor Index fell 12.25% to 9,011.14 — its second-biggest fall on record, according to Reuters — and about $2 trillion was wiped off the Nasdaq’s market value in a single day. Nvidia fell 9.26% to $181.60, erasing roughly $447 billion of value, wiping out its gains for the year and leaving it about 24% below its October peak. SanDisk plunged 22%, Micron and AMD each fell about 17%, Marvell fell about 17%, Broadcom fell 10% and Intel about 10%. Tesla fell 10.8%.

Why now: the election, read twice

The trigger was not an earnings miss or a product failure. It was a second reading of the midterm election. On Wednesday the market read the Democrats’ sweep and bought — the Nasdaq rose 1.4%. On Thursday it read the same results again and sold, as investors focused on what the sweep could mean for the AI data-center buildout: moratorium proposals and ballot measures that could slow new data centers. The Texas governor’s race had already made data centers a live campaign issue.

Qualcomm added fuel with a weak outlook, citing an ongoing shortage of memory components for smartphones — a warning that landed the same day memory stocks were being sold off anyway.

That is the paradox at the center of the day. The memory shortage is real: SK Hynix is sold out through 2029, and the RTX 5090 was selling in the US at $9,400 — 370% above its official price — as this site covered in October and earlier this week. Memory makers fell hardest on the same shortage that is supposed to be making them rich, because the market was not repricing the shortage. It was repricing what investors had been willing to pay for it.

No company cancelled a product, lost a customer or broke its business on November 5, and no new law passed. This was a repricing of expectations, not a confirmed change in policy or demand.

Friday morning: the aftershock went global, then bounced

The selloff did not stop at the US close. South Korea’s KOSPI fell more than 8% at the open on Friday, and the exchange froze all trading for 20 minutes. By Friday morning in the US, the mood had turned again: Nasdaq futures were up about 1.4%, the Roundhill Memory ETF was up almost 7%, and Cloudflare — which reported strong results after Thursday’s close — was up nearly 20% in premarket trading, according to Investopedia.

The Wall Street Journal, cited by Investopedia, reports that some investors are now skeptical Anthropic can pull off the $1.5 trillion valuation expected for its IPO, after this week’s rout. Anthropic is expected to go public this year; OpenAI is targeting 2027.

The judgment

Bubble or correction is the wrong binary for a single day. What Thursday proved is narrower and more useful: the AI trade’s price assumed the buildout could only accelerate, and one election re-read was enough to take $2 trillion off that assumption. The demand question — whether data centers keep getting built and filled — is unchanged this week. The policy question is now open in a way it was not.

Watch two things. First, whether any actual moratorium or ballot measure advances beyond talk into something that slows a real project. Second, whether the next round of chipmaker earnings and data-center capex guidance holds or bends. If both hold, Thursday was a correction — a violent one, but a correction. If either bends, it was the start of something else.

Market figures in this post are the November 5, 2026 closing values.