Three of the companies most tied to Anthropic’s business will open their own books within days of its IPO paperwork. Anthropic could make its S-1 public as early as Monday, The Information reported Sunday evening, and the Claude maker’s three cloud partners all report quarterly results later in the week.
Microsoft reports after the close Wednesday, and Alphabet holds its call at 4:30 p.m. ET the same day. Amazon follows on Thursday. Reuters has described Google and Amazon as investors, suppliers of computing power and distribution partners, as well as AI competitors.
Nothing was on file yet as of early Sunday evening. Anthropic submitted its draft confidentially on June 1, and an EDGAR search shortly after 6 p.m. ET showed no public Anthropic registration statement. IFR reported this month that the company planned to file publicly on Oct. 26, launch its roadshow Nov. 9 and price the deal the following week, targeting up to $100 billion at a $2 trillion valuation. Morgan Stanley and Goldman Sachs are the joint bookrunners, IFR said.
How much of Anthropic runs through its cloud partners
The confidential draft already gave a partial answer. In 2025, about $2.16 billion of sales, or 47% of revenue, went through the Amazon and Google cloud marketplaces, Reuters reported in late September after seeing a copy. A Reuters analysis put the platforms’ cut at roughly $351 million, about 16 cents on each dollar. The two companies also collected 60% of the $909 million in customer bills Anthropic had outstanding at year-end.
The obligations run the other way, too. A later draft reviewed by The Wall Street Journal listed roughly $450 billion in cloud compute agreements over the next decade, including $111 billion with Google Cloud, $110 billion with AWS and $31 billion with Microsoft. In the copy Reuters saw, Anthropic said its reliance on a small group of partners and suppliers “creates complex dynamics that could give rise to conflicts of interest and adversely affect our access to compute.”
The Information’s editors want the public version to pin down what Anthropic pays Google and Amazon to run its models, how much each has invested and how far those stakes have risen. Amazon CEO Andy Jassy said on an Andreessen Horowitz podcast published Friday that AWS is “largely sold out” of computing capacity through the end of next year, the publication noted.
What investors still can’t see
Third-quarter revenue rose 45% to $16.8 billion from $11.6 billion, IFR reported, after growing more than 140% from the first quarter to the second. After the slowdown, some investors discussed a valuation near $1.5 trillion, down from about $2 trillion.
Customer concentration is another open item. Two unnamed customers each brought in 12% of 2025 revenue, according to Reuters, and the Journal found that about a fifth of the $16.3 billion booked in the first half came from two customers. The Information also wants to see how Anthropic would settle conflicts between the Long-Term Benefit Trust, which appoints most of the board, and directors named by the co-founders, who under a plan it reported would hold a combined 50.1% of voting power. It has also reported that Anthropic has weighed a lockup longer than the usual 180 days, with an exception for some holders to sell at the listing.
A once-busy fall calendar for tech IPOs is down to Anthropic, Reuters said. Switch and Nscale have pushed their IPO plans back, Reuters reported Thursday. Other issuers are reluctant to compete with Anthropic for institutional investors’ attention and capital, two people familiar with the matter told the agency.