Markets are eagerly awaiting the public listings of OpenAI and Anthropic, but renowned short seller Steve Eisman views these two AI giants as the most vulnerable element in the entire AI trade chain. Anthropic is pushing hard for an initial public offering (IPO), with its valuation and fundraising scale potentially surpassing the record-breaking launch of SpaceX earlier this summer. Reports suggest its valuation could be as high as $2 trillion, which would place the Claude model developer among the world's most valuable companies if achieved.

However, Eisman, the trader famed for betting against the housing market in "The Big Short," is concerned that the current AI trade is overly dependent on the success or failure of just two companies. "If there's an Achilles' heel to the whole story, it lies with Anthropic and OpenAI — if something goes wrong with those two," Eisman said in an interview. He warned that if cheaper models from China begin to capture market share, it could trigger a price war, stating, "then we'll have a problem."

After years of driving stock indices to new highs, the AI trade has once again proven its role as a market engine in 2026, but concerns about the sustainability of this investment frenzy are also growing. "The issue is that, as far as I understand, about 70% of AI revenue from giants like Microsoft, Amazon, Google, and Oracle comes from Anthropic and OpenAI — just those two," Eisman said. "In a sense, the future of these giants is essentially a bet on the success of OpenAI and Anthropic."

Eisman is not the first to express concern about the financial health of these two AI leaders. Independent researcher and journalist Ed Zitron warned earlier this summer that OpenAI could become the "Lehman Brothers" of the AI trade — if it hits a setback, it could pose a systemic risk, dragging down other companies.

Meanwhile, the rise of Chinese open-weight models, represented by Kimi K3, sparked panic on Wall Street last month, causing chip stocks to plunge due to fears of intensified competition in the AI market. However, similar to the situation when DeepSeek emerged in January 2025, the losses have mostly been recovered, and market sentiment has calmed. The Philadelphia Semiconductor Index is up 75% year-to-date.

Despite his concerns, Eisman clarified that he is not yet ready to make a judgment on a price war between OpenAI, Anthropic, and Chinese rivals — at least not until he has more information about the financial conditions of the two companies. "Just wait until Anthropic goes public, then we'll see the real data and track their performance every quarter," he said. "Until then, it's all just hearsay."