Concerns are mounting over a potential investment bubble in the artificial intelligence (AI) sector, as recent market developments raise questions about the sustainability of funding for AI infrastructure companies. The sharp decline in share prices across a range of firms and heightened borrowing costs are prompting caution among investors who had previously been enthusiastic about the once-rapidly expanding industry.

Key players such as Nvidia and Oracle have seen their shares fall by around 10 percent since earlier this month, reflecting shrinking confidence even among established technology giants. More severely affected are lesser-known companies specializing in AI infrastructure, often referred to as "neoclouds." These firms, including CoreWeave, Nebius, and Iren, have faced significant sell-offs amidst concerns over heavy losses and growing debt burdens.

Unlike large hyperscale companies such as Microsoft and Amazon that leveraged profitable core businesses to develop AI infrastructure, neoclouds depend heavily on substantial fundraising efforts—often through issuing billions in debt—to finance their rapid expansion. CoreWeave, for example, has raised approximately $32 billion in debt and equity to build 51 data centers but generated revenue of only $4.6 billion in the first half of this year. Similarly, UK-based Nscale has secured nearly $10 billion in debt within just two years of operation, relying on future contracts worth over $100 billion to justify such high borrowing.

Market dynamics have shifted recently due to rising global interest rates driven by inflation concerns and a tightening of capital availability. Analysts at Barclays note that while early AI adopters like OpenAI and Anthropic previously pursued data center capacity aggressively, they are now taking a more measured approach, seeking “capacity at an acceptable return.” This shift threatens to place downward pressure on prices and profitability for neocloud operators.

Nvidia CEO Jensen Huang offered a contrasting perspective, stating that demand for neocloud services remains extremely strong but that a “scarcity of capital” is hindering growth. However, borrowing costs for these companies are rising sharply, with interest rates on some CoreWeave debt briefly reaching 16 percent, raising doubts about the feasibility of sustained debt financing in the current environment.

HSBC analysts have sharply critiqued CoreWeave’s financial outlook, estimating its investment returns fall short of borrowing costs, potentially prolonging losses into 2029 and eroding shareholder value. Market responses include share price declines of approximately 33 percent for CoreWeave in recent weeks, canceled IPOs such as Australian data center company Firmus’s aborted £20 billion offering, and speculation about others like Singapore’s DayOne following suit. The London-based firm Nscale, which has received government backing, remains committed to an IPO despite moderated valuation expectations.

Some industry experts warn that these troubles could trigger a “death spiral” for neoclouds if ongoing investments fail to generate sufficient revenue for debt servicing. Gartner analyst Will Sommer projects that by 2030, as much as $3.5 trillion in AI infrastructure spending may be written off, with an estimated 80 percent of neocloud companies ceasing independent operations, either through acquisitions or closures.

The unfolding situation underscores unease over whether the strains are limited to a segment of younger infrastructure companies or might threaten the broader AI boom that has underpinned recent stock market gains and economic activity. Analyst Joachim Klement describes neoclouds as the “weakest link in the chain,” suggesting their struggles may signal growing instability within the AI sector’s financial foundation.