Investor Steve Eisman warned that the artificial intelligence boom has become increasingly dependent on the fortunes of just two companies: OpenAI and Anthropic. Eisman, known for his bet against the housing market ahead of the global financial crisis, said the two AI startups account for roughly 70% of AI-related revenue at Microsoft, Amazon, Alphabet’s Google and Oracle, and as much as 25% to 35% of their cloud revenue. Speaking late Tuesday on CNBC’s “Fast Money,” he said the futures of these massive companies are, in a sense, a bet that OpenAI and Anthropic will succeed. Eisman identified China as the biggest potential revenue threat, noting that Chinese open-source AI models are significantly cheaper and appear to be gaining market share. He said the Achilles’ heel is if something bad happens to Anthropic and OpenAI, and Chinese open-weight models start taking a lot of market share, which he hears they are starting to do, a big price war could result. Eisman’s warning adds to a debate over whether the extraordinary spending behind the AI boom can generate sufficient returns. Investor Michael Burry, also chronicled in “The Big Short,” has taken a more bearish view, questioning whether much of current and future AI demand comes from end customers and arguing that a significant portion is financed through circular arrangements. Burry has placed bearish bets against beneficiaries of the AI boom, including Nvidia, and others positioned against the broader semiconductor sector.