Anthropic May Get a Junk Credit Rating After Its IPO, Blackstone Warns

Anthropic, the AI company behind Claude, is likely to receive a junk credit rating even after its planned IPO, Blackstone has told investors — a warning that raises the cost of funding the largest AI buildout in history. The assessment, reported by the Financial Times and covered by Invezz, marks a sharp shift: Blackstone previously expected Anthropic to win an investment-grade rating before the end of the year.

What happened

Blackstone is an anchor investor in Project North Star, the $63 billion financing that funds Anthropic's lease of 1.5 gigawatts of Google semiconductors co-developed by Broadcom. According to people familiar with the matter cited by the Financial Times, Blackstone has now told investors in that deal that the major rating agencies are likely to place Anthropic in the double-B range — the top tier of junk, but still below investment grade — after the company lists.

Anthropic filed to go public earlier this week, setting up what is expected to be one of the largest listings of the year, with a November debut anticipated. The credit warning landed in the middle of a brutal week for AI stocks, and coverage of Friday's tech selloff cited the report as one of the factors that blunted optimism around the AI trade, according to Dimsum Daily.

Why a junk rating matters

A credit rating decides how cheaply a company can borrow. Investment-grade borrowers — rated BBB-minus or above — can sell debt to almost anyone, including pension funds and insurers. Junk-rated borrowers pay higher interest and face a smaller pool of buyers, because many insurers and pension funds are restricted from holding large positions in high-yield debt.

For Anthropic, the stakes are unusually large. Its listing documents describe plans to spend more than $800 billion on computing infrastructure through 2045. Even a small difference in borrowing costs, compounded across spending on that scale, runs into billions of dollars — and a junk rating makes every future data-center deal harder to finance directly.

How Project North Star works around the problem

The $63 billion deal itself shows how Anthropic already borrows around its credit profile, as detailed by BigGo Finance. More than $42 billion of senior loans are guaranteed by Broadcom, which holds a high investment-grade rating, making that debt accessible to institutional investors. The remaining roughly $18 billion of junior debt is backed by Anthropic's own lease payments — and it is priced like junk: the junior tranche carries a double-B-plus rating with a positive outlook from KBRA, a double-B rating from Morningstar DBRS, and Blackstone's funds invested $9 billion of it at a yield above 10 percent.

Notably, Fitch, Moody's and S&P — the three agencies that matter most for corporate borrowing costs — have not yet issued formal ratings for Anthropic. Blackstone's warning is based on guidance from those agencies, not a final decision.

Why it's blowing up now

The warning arrives just as investors have turned skeptical about AI spending. This week the Nasdaq suffered its worst month since March 2025 as Alphabet, Amazon and Intel results raised the same question from different angles: the buildout is enormous, the cash burn is real, and the returns are not yet visible. Anthropic's own prospectus reported $16.3 billion of first-half revenue alongside a large accounting-driven net loss. A junk rating would confirm, in the bond market's language, what equity investors spent October worrying about — that the AI boom's financing costs are rising faster than its proven profits.

It also sets up a contrast inside the AI race. Anthropic's rivals face the same scrutiny over data-center debt, and bankers are reportedly working on similar financing structures for OpenAI. If the first big AI listing carries a junk rating, every following deal gets priced against it.

What's next

Watch three things. First, whether Fitch, Moody's or S&P publish a formal rating before the listing, and where it lands within the double-B range. Second, whether Anthropic keeps relying on supplier-guaranteed structures like Project North Star, or tests the bond market in its own name. Third, how the IPO itself is priced: equity investors may pay up for growth that bond investors are grading as speculative. None of this changes what Anthropic builds — it changes what the building costs.

FAQ

What credit rating is Anthropic expected to get?

Blackstone has told investors Anthropic is likely to land in the double-B range — the highest tier of junk, below investment grade — based on guidance from the major rating agencies, though no formal rating has been issued yet.

What is Project North Star?

It is a $63 billion financing that funds Anthropic's lease of 1.5 gigawatts of Google TPUs co-developed by Broadcom. Over $42 billion of senior debt is guaranteed by Broadcom; about $18 billion of junior debt rests on Anthropic's lease payments.

Why does a junk rating matter for an IPO?

It raises borrowing costs and shuts out many pension funds and insurers that cannot hold much high-yield debt, forcing a company with more than $800 billion of planned infrastructure spending to rely on costlier or indirect financing.

Has any agency officially rated Anthropic?

Not the big three: Fitch, Moody's and S&P have issued no formal rating. KBRA rated the Project North Star junior debt BB+ with a positive outlook, and Morningstar DBRS rated it BB.

Sources: Invezz, BigGo Finance, Dimsum Daily.