Global stocks sell-off as AI valuation concerns persist ahead of Nvidia earnings

Global stock markets experienced a significant downturn on Tuesday as investors grappled with concerns over inflated valuations and an uncertain economic landscape. The pan-European Stoxx 600 index opened lower, with mining and banking sectors contributing notably to Europe's declines. The Stoxx Europe 600 Technology Index fell by 1.4%, mirroring the declines seen in U.S. markets, where fears of a potential artificial intelligence bubble continue to loom large. All three major U.S. stock indexes—the Dow Jones Industrial Average, the S&P 500, and the tech-heavy Nasdaq Composite—closed in the red during the previous trading session. Asian markets followed suit, with significant losses in Japan and South Korea's benchmark indexes. Mike Gallagher, director of research at Continuum Economics, indicated that this market behavior could result in equities dropping approximately 5% from their recent peaks, suggesting it may be a natural phase of profit-taking after a robust market rally since April. This sell-off occurs against the backdrop of ongoing AI bubble fears, with investors anxiously awaiting Nvidia's third-quarter earnings report, scheduled for release after Wednesday's market close. Nvidia is considered a crucial indicator for the AI sector, as numerous leading companies depend on its GPU technology. Gallagher noted that ongoing earnings reports show major companies, particularly hyperscalers, are still generating substantial revenue projections through 2026-27. He highlighted that Meta is under scrutiny, as its lack of a server business could signal whether the next wave of AI innovations will produce tangible revenue. Yuri Khodjamirian, Chief Investment Officer at Tema ETF, attributed the market's decline to a cautious skepticism. He remarked that the recent mega-deals announced over the summer require actual funding, prompting market participants to reassess their expectations. He referenced OpenAI's significant commitments to GPU expenditures and data center power, stating that the market is beginning to understand that the rollout may be slower than initially anticipated. Khodjamirian emphasized that the ongoing market adjustments indicate a healthy correction, pointing to Oracle's stock price returning to pre-OpenAI announcement levels as a sign of stability. The trend among major companies, including Microsoft, Meta, and Nvidia, remains upward, suggesting continued growth in data center investments. However, Gallagher cautioned that investors are also engaging in de-risking strategies amid a challenging macroeconomic environment. There is uncertainty surrounding a previously anticipated Federal Reserve rate cut in December, with expectations now leaning towards a pause in the first quarter of 2026. Additionally, the U.S. Supreme Court's upcoming decisions on Trump's reciprocal tariffs could influence market dynamics significantly. As the market contemplates these developments, Gallagher noted that a major sell-off would likely require substantial negative news, which has yet to materialize. In the cryptocurrency realm, leverage has caused some exaggeration, with Bitcoin experiencing a 25% decline from its October peak and Ether down 35% since August. Khodjamirian adopted a long-term perspective, highlighting a critical issue concerning access to electricity for data centers. He pointed out that executives globally recognize the necessity of power for these facilities, which could pose significant challenges to the AI revolution and other sectors, including electric vehicles and digital currencies.