Panmure Liberum strategist warns AI bubble could drag S&P 500 to 5,000

Key Findings

Joachim Klement, head of market strategy at Panmure Liberum, has warned of a potential AI bubble that could lead to a significant decline in the tech sector. His projections suggest that the S&P 500 could drop by over 35% to 5,000 by the end of 2027.

The Math Behind the Bearish Call

Klement's analysis is based on the shrinking free cash flow at hyperscalers and rising debt costs. He estimates that these companies would need to add $2-5 trillion in annual revenue to justify their spending. This is a significant increase from the current market value of these companies.

Industry Comparison

Klement's warnings are not limited to the US tech sector. He also expects European and UK equities to suffer in the event of a tech downturn. This is because the same factors that contribute to a decline in the US tech sector can also affect other countries.

Historical Context

Klement's warnings are not new. He has been consistently bearish on the tech sector, particularly when it comes to AI spending. In August 2026, he described himself as "very bearish" on AI capex on CNBC.

Scenarios and Implications

Klement has identified two possible scenarios: a pullback and a full crash. A pullback of 4.5-6% in tech spending could lead to a 20% decline in the S&P 500, while a full crash could result in a decline of over 70% in tech hardware stocks. These scenarios have significant implications for investors, particularly those with exposure to the tech sector.

Conclusion

In conclusion, Klement's warnings highlight the potential risks associated with the current AI boom. Investors should be cautious and monitor the situation closely, as the future is inherently uncertain.