AI stock sell-off drops S&P 500 more than 4%, worst day since Trump's tariff announcements in 2025
Published . Updated .
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A brutal sell-off swept through Wall Street Thursday, led by stocks tied to the buildout of AI data centers. The wipeout more than erased the U.S. stock market’s gain from the day before, which was its best in three months.
Directly affected
- No company is named in this report.
Indirectly affected
- QQQ Invesco QQQ-9.8% 30d
Invesco QQQ: it holds the big tech and AI names. Linked by “ai” (AI and big tech) in this story.
- AIQ Global X Artificial Intelligence & Technology ETF-1.9% 15d
Global X Artificial Intelligence & Technology ETF: it holds the big tech and AI names. Linked by “ai” (AI and big tech) in this story.
- XLI Industrial Select Sector SPDR-0.3% 30d
Industrial Select Sector SPDR: it holds companies hit by import costs and trade rules. Linked by “tariff” (tariffs and trade) in this story.
- MSFT Microsoft+11.8% 30d
Microsoft (prepackaged software): big tech's AI spending and demand drive its shares. Linked by “ai” (AI and big tech) in this story.
- GOOGL Alphabet-15.6% 30d
Alphabet (computer programming, data processing, etc.): big tech's AI spending and demand drive its shares. Linked by “ai” (AI and big tech) in this story.
- AMZN Amazon.com+6.7% 30d
Amazon.com (catalog and mail-order houses): big tech's AI spending and demand drive its shares. Linked by “ai” (AI and big tech) in this story.
- META Meta Platforms-19.0% 30d
Meta Platforms (computer programming, data processing, etc.): big tech's AI spending and demand drive its shares. Linked by “ai” (AI and big tech) in this story.
- CAT Caterpillar-26.6% 30d
Caterpillar (construction machinery and equip): importers and exporters pay or lose sales when tariffs change. Linked by “tariff” (tariffs and trade) in this story.
Price reaction, T-5 to T+3
| Ticker | T-5 | T-3 | T-1 | T0 | T+1 | T+2 | T+3 |
|---|---|---|---|---|---|---|---|
| QQQ | +6.56% | +5.75% | base | after close | after close | after close | after close |
| AIQ | +6.96% | +5.95% | base | after close | after close | after close | after close |
| XLI | +3.03% | +5.45% | base | after close | after close | after close | after close |
| MSFT | -2.67% | -2.88% | base | after close | after close | after close | after close |
| GOOGL | -0.97% | -0.97% | base | after close | after close | after close | after close |
| AMZN | -7.79% | -3.81% | base | after close | after close | after close | after close |
| METANo price data for this ticker | — | — | — | — | — | — | — |
| CAT | +12.53% | +12.71% | base | after close | after close | after close | after close |
Closing-price change versus T-1, the last close before the story. T0 to T+3 fill in after each market close. Prices: Alpaca IEX.
AI stock sell-off drops S&P 500 more than 4%, worst day since Trump's tariff announcements in 2025 Juneau Independent
Source: Juneau Independent
This story
| Company | When | Move | Status |
|---|---|---|---|
| AIQ | three days earlier | +5.95% | final price |
| AIQ | five days earlier | +6.96% | final price |
| AMZN | three days earlier | -3.81% | final price |
| AMZN | five days earlier | -7.79% | final price |
| CAT | three days earlier | +12.71% | final price |
| CAT | five days earlier | +12.53% | final price |
| GOOGL | three days earlier | -0.97% | final price |
| GOOGL | five days earlier | -0.97% | final price |
| MSFT | three days earlier | -2.88% | final price |
| MSFT | five days earlier | -2.67% | final price |
| QQQ | three days earlier | +5.75% | final price |
| QQQ | five days earlier | +6.56% | final price |
| XLI | three days earlier | +5.45% | final price |
| XLI | five days earlier | +3.03% | final price |
Congressional trades in the stocks in this story
- Rep. Pete Sessions sold Microsoft (MSFT) (held by a spouse), worth $250,001 - $500,000 on 2 Oct 2026. That is 34 days before publication. Filed 27 Oct 2026. View the filing.
- Rep. Lisa McClain bought Microsoft (MSFT) (held by a spouse), worth $1,001 - $15,000 on 30 Sep 2026. That is 36 days before publication. Filed 12 Oct 2026. View the filing.
- Rep. Michael Rulli sold Microsoft (MSFT), worth $1,001 - $15,000 on 28 Sep 2026. That is 38 days before publication. Filed 2 Oct 2026. View the filing.
- Rep. Pete Sessions sold Alphabet (GOOGL), worth $15,001 - $50,000 on 14 Sep 2026. That is 52 days before publication. Filed 18 Sep 2026. View the filing.
- Rep. Rohit Khanna sold Alphabet (GOOGL) (held by a spouse), worth $1,001 - $15,000 on 4 Sep 2026. That is 62 days before publication. Filed 7 Oct 2026. View the filing.
- Rep. Thomas H. Kean Jr sold Alphabet (GOOGL), worth $1,001 - $15,000 on 27 Aug 2026. That is 70 days before publication. Filed 12 Sep 2026. View the filing.
- Rep. Pete Sessions sold Amazon Com (AMZN), worth $15,001 - $50,000 on 27 Oct 2026. That is 9 days before publication. Filed 27 Oct 2026. View the filing.
- Rep. Pete Sessions sold Amazon Com (AMZN) (held by a spouse), worth $100,001 - $250,000 on 2 Oct 2026. That is 34 days before publication. Filed 27 Oct 2026. View the filing.
- Rep. Michael T. McCaul sold Amazon Com (AMZN) (held by a spouse), worth $1,001 - $15,000 on 28 Aug 2026. That is 69 days before publication. Filed 14 Oct 2026. View the filing.
- Rep. Maria Elvira Salazar sold Meta Platforms (META), worth $1,001 - $15,000 on 24 Sep 2026. That is 42 days before publication. Filed 7 Oct 2026. View the filing.
- Rep. Rohit Khanna bought Meta Platforms (META) (held by a dependent child), worth $1,001 - $15,000 on 23 Sep 2026. That is 43 days before publication. Filed 7 Oct 2026. View the filing.
- Rep. Maria Elvira Salazar bought Meta Platforms (META), worth $1,001 - $15,000 on 22 Sep 2026. That is 44 days before publication. Filed 7 Oct 2026. View the filing.
Public disclosure filings, not a recommendation. The filing link is the source document. News use of these reports still sits under 5 U.S.C. § 13107(c).
This story
12 out of 100
“AI stock sell-off drops S&P 500 more than 4%, worst day since Trump's tariff announcements in 2025” scores 12 out of 100. The score uses 1 sources.