Anthropic IPO Valuation Cut to $1.5 Trillion as Revenue Growth Slows

The most anticipated stock market debut in tech history just got a colder reception than expected. According to a Reuters exclusive published October 15, 2026, investors who attended Anthropic's pre-IPO investor day in San Francisco are now discussing a valuation of around $1.5 trillion for the AI company's planned November listing — a significant step down from the roughly $2 trillion valuation previously expected.

The reason is not that Anthropic is doing badly. It is that it is no longer accelerating as fast as the market assumed.

The numbers behind the rethink

At Wednesday's investor day, Anthropic told prospective investors that third-quarter revenue jumped 45% to $16.8 billion from the previous quarter, and that the company was profitable on an adjusted basis during the quarter. For a company that recorded an $8 billion operating loss on just $4.6 billion of annual revenue last year, that is a genuine turnaround.

But investors focused on the trend, not the level. Revenue more than doubled from the first quarter's $4.7 billion to $11.6 billion in the second quarter — then grew 45% in the third. Still spectacular by any normal standard, yet a clear deceleration. In a market that had priced in ever-accelerating growth, the slowdown was enough to shave half a trillion dollars off expectations.

The meeting drew mostly prominent existing investors, who sat down with chief executive Dario Amodei and finance chief Krishna Rao at the company's San Francisco headquarters. Four people familiar with the matter described the discussions to Reuters on condition of anonymity.

Why this IPO is a bellwether

Anthropic's listing is widely seen as the test case for the entire AI financing boom. As Reuters noted, a cooler reception could weigh on the wider AI market, whose near-term prospects investors see as hinging largely on the share sale's success — followed by OpenAI's potential listing next year.

The timing is delicate. The Reuters report landed amid broader concerns over the ballooning cost of financing AI, alongside tech sector selloffs and delayed offerings. Anthropic had even pitched investors on seeing over $30 trillion in potential long-term revenue, according to an earlier Wall Street Journal report — a figure that now looks like part of the expectations-reset problem.

What to watch next

Three things will decide whether $1.5 trillion sticks. First, whether growth re-accelerates in Q4 — the company needs to show the Q3 slowdown was a blip, not a ceiling. Second, whether the IPO prices and then trades well in its first weeks; a weak debut would ripple straight into OpenAI's 2027 plans. Third, whether enterprise AI spending — the core of Anthropic's revenue — keeps expanding as companies move from pilots to production.

A $1.5 trillion IPO would still rank among the largest listings ever. But the message from San Francisco is clear: in late 2026, investors are done paying for AI growth stories on faith. They want the growth curve to keep bending upward — and they are now checking the math.

For more on the AI industry's turbulent week, see Anthropic's rogue AI agents briefing the White House and Salesforce's "SIForce" superintelligence rebrand.

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