Billionaire Citadel founder Ken Griffin told Bloomberg that the AI market is 'almost certainly' in a bubble, and the article notes that Alphabet, Amazon, Microsoft and Meta aim to spend more than $700 billion on infrastructure this year, fueling investor doubts about returns. It points out that the S&P 500 has gained nearly 100% since the start of 2023 and that the Shiller CAPE ratio suggests stocks are near a peak. Comparing with the dot-com bubble of 2000, the author argues the crash looks small in the long-term chart, and Amazon fell from about $5 a share to under $1 before trading above $260 today. The author says the market may decline in coming weeks or months, but argues it has historically recovered and that patience with quality stocks may be rewarded over time.
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artificial intelligencevaluationS&P 500Ken Griffin
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Related tickers and likely impact
QQQ
▼ Likely negativeInvesco QQQ Trust
Relevance: low
| Market | US stocks |
|---|---|
| Sector | ETF |
| Close on 10/23/2026 | 704.39 |
| Change that session | -0.01% |
SPY
▼ Likely negativeSPDR S&P 500 ETF
Relevance: low
| Market | US stocks |
|---|---|
| Sector | ETF |
| Close on 10/23/2026 | 759.85 |
| Change that session | -0.54% |
Impact is scored by AI from the headline and may be wrong. It is not investment advice.
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