US Stocks Plunge on Inflation Fears, Bitcoin Miners Among Hardest Hit Tech Firms

US equities experienced their most significant single-day decline since July on Wednesday, as hotter-than-expected inflation data rattled investors and triggered a broad selloff across technology and artificial intelligence (AI) infrastructure companies. Bitcoin miners, many of which have diversified into AI services, were among the hardest hit, with several firms seeing their shares plummet by more than 12%.

The S&P 500, a key benchmark for US stocks, shed 1.1%, marking its largest drop since July 29. The technology-heavy Nasdaq Composite fared worse, falling 1.9% in its steepest decline since July 23. The Dow Jones Industrial Average, in contrast, registered a more modest 0.1% dip.

Inflation Fuels Market Anxiety

The catalyst for the market's downturn was the release of US consumer price index (CPI) data for September, which showed a 3.7% year-over-year increase. This figure surpassed economists' expectations of 3.6% and remained well above the Federal Reserve's long-term 2% target. Higher gasoline prices, attributed to the ongoing Middle East conflict, were cited as a significant contributor to the elevated inflation.

The inflation report immediately heightened expectations for an October interest rate hike by the Federal Reserve. The implied probability of such a move briefly exceeded 50% on Wednesday before receding. However, San Francisco Federal Reserve President Mary Daly indicated that while further rate increases might be necessary to control inflation, there was no immediate urgency for action this month. "I don't feel urgent that we have to decide with a limited set of information. I think we have the time that we need," Daly stated.

AI Infrastructure and Bitcoin Miners Hit Hard

The impact of rising inflation and potential higher interest rates was particularly acute for companies in the AI infrastructure sector, many of which rely heavily on debt financing to fund their data center expansions. Increased borrowing costs could significantly impact their growth strategies and profitability.

Among the leading decliners in the technology space were data center operator CoreWeave, which saw its shares fall 16%, AI infrastructure provider Nebius, down 11%, and tech giant Oracle, which dropped 9%. PRISM's AI Data Center and Infrastructure Index, which tracks 23 AI infrastructure stocks, reported that 21 of its constituents declined on Wednesday, with an average loss of 7.46%.

The selloff extended directly to Bitcoin mining companies, several of which have strategically expanded their operations to include AI infrastructure. TeraWulf shares fell 12.64%, while Core Scientific, Cipher Mining, and IREN experienced declines of 12.44%, 12.35%, and 12.2% respectively. Other prominent miners, including Riot Platforms, Bitdeer Technologies, Marathon Digital Holdings (MARA), and CleanSpark, also recorded losses during the session. The broader cryptocurrency market also saw a dip, with Bitcoin price falling below $82,000.

Why it matters

The market's sharp reaction underscores investor sensitivity to persistent inflation and the potential for tighter monetary policy from the Federal Reserve. For the rapidly expanding AI infrastructure sector, higher interest rates translate directly into increased costs for the substantial capital investments required for data center build-outs. This dynamic is particularly relevant for Bitcoin miners, many of whom have diversified their revenue streams into AI computing, making them susceptible to both cryptocurrency market fluctuations and broader macroeconomic pressures affecting tech valuations.

What to watch

Investors will closely monitor upcoming inflation data and statements from Federal Reserve officials for further clues on the trajectory of interest rates. The performance of AI infrastructure companies and Bitcoin miners will likely remain tied to these macroeconomic indicators, alongside developments in the crypto market and the specific demand for high-performance computing. Any signs of easing inflation or a shift in the Fed's hawkish stance could provide relief, while continued price pressures might extend the current market caution.