Anthropic's $16.3 Billion Filing Reignites the AI Stock Rally

Anthropic's S-1 filing shows first-half revenue of $16.3 billion — nearly 14 times last year's figure — and Wall Street rushed back into AI stocks on the news. The Nasdaq Composite closed Tuesday up 1.2%, adding to Monday's 0.8% gain on the day the company filed for its initial public offering.

The rally reversed a sustained selloff driven by fears of overspending and unsustainable debt across the sector. Anthropic's prospectus pointed to a healthier financial position than some investors feared, and the relief trade lifted the names hit hardest in recent weeks.

Nebius Group jumped 11.2% and CoreWeave rose 8% on Tuesday — even as Elon Musk predicted over the weekend that capital access would shrink and forecast "guppy-level death" for the new-age cloud providers. Storage makers climbed too: Western Digital gained 7% and Seagate Technology Holdings added 3.7%.

What does the filing actually change for investors?

Louis Navellier, an analyst at InvestorPlace, said the S-1 "is generating a lot of excitement" in a note to clients. The registration statement offered increased transparency on Anthropic's business model and revealed growth he called "stunning" — despite ongoing operating losses. Navellier expects a "grossly oversubscribed" IPO, meaning total demand for shares could exceed what's made available.

Rob Thummel, a senior portfolio manager at Tortoise Capital, told MarketWatch that as investors dig into the report, they're finding the same factors that powered AI infrastructure stocks earlier this year. Anthropic is making "significant commitments to capital spending for an extended period of time," he said. As demand for computing power rises, so will demand for the infrastructure supporting it — including the neoclouds that rent out computing capacity.

The read-through hit hardware broadly on Tuesday:

• Dell Technologies, lifted all year by AI server enthusiasm, closed up 7.5%.
• Optical stocks extended Monday's gains, with Coherent up 6.4% and Lumentum Holdings up 5.9%.
• Connectivity providers Credo Technology and Astera Labs climbed 10.8% and 10.5%, respectively.

Thummel also flagged Anthropic's contracts to secure computing power in the future, saying they reflect confidence that demand for AI infrastructure "will continue to be tremendous for a while."

Celine Woo, portfolio manager at Lazard Asset Management, told MarketWatch the pricing and demand picture remains unclear, but the IPO itself is a bullish signal. "There's still ample appetite in the market from the investor's point of view to own this part of the business model," she said.

Earnings season is reinforcing the trade

The Anthropic filing isn't the only tailwind. ASML and Taiwan Semiconductor Manufacturing Co. both posted earnings beats on unrelenting demand for advanced chip technologies, each offering an "optimistic outlook" for the sector, Michael Field, Morningstar's chief European equity strategist, wrote in a Monday note.

The Big Tech companies driving the AI spending surge show no sign of slowing either. After a strong earnings report last week, Meta announced plans on Monday to raise up to $95 billion through equity offerings. Alphabet, Microsoft and Amazon.com all report earnings later this week — results that will test whether the renewed confidence in sustained AI capex holds up.