In June, Kroll Bond Rating Agency put an issuer rating of BB+ on Anthropic. One notch below investment grade. The highest speculative rung, not the weakest. The documents, seen by the Financial Times, had not been reported. The rating came ahead of a $35 billion chip financing led by Apollo. About $4.4 billion of junior debt, exposed to Anthropic’s credit risk, was rated BB+ with a stable outlook and sold at a yield of about 8.5%. The rest was guaranteed by Broadcom. Senior debt, 5.75%.

KBRA did not run full financial models. It used a “risk score”. Anthropic supplied first-quarter 2026 revenue, adjusted operating income, the annualised run-rate and an internal second-quarter forecast. It did not supply free cash flow. It did not supply EBITDA. Analysts estimated those. At the time of the rating the firm put second-quarter revenue at $10.9 billion. People familiar with the figures told the FT it came in at $11.5 billion. At the end of June, on its own balance sheet, debt was zero. The risk sat with partners and special-purpose vehicles.

It could issue, to lease Broadcom semiconductors, up to $42 billion of convertible notes. The detailed terms were not given to KBRA. Wall Street banks were assembling, at the same time, a $60 billion package for custom Google/Broadcom chips, of which $18 billion junior, backed by Anthropic’s chip-rent payments. That is the credit map, not the listing valuation. Bankers for Anthropic and OpenAI have lobbied the large agencies for investment-grade ratings after an IPO. Anthropic expects, over the next decade, more than $500 billion of compute and infrastructure spend.

The caveats sit in the same paragraph as the figure. KBRA is smaller than Moody’s, S&P and Fitch. The rating rests on company-selected disclosure. Growth is slowing against earlier in the year. KBRA and Anthropic declined to comment. Anyone who takes BB+ as an open door to prime markets skips the method. Anyone who takes it as insolvency skips the notch.

On another thread, Bloomberg wrote in September that Anthropic was finalising an expansion of its revolving credit line towards $15 billion, above a target of about $10 billion. Morgan Stanley is leading. Goldman Sachs, JPMorgan and Citigroup have visible roles. The four banks are also leading the IPO preparation. The firm had confidentially filed, in June, its US listing papers. The line is a different instrument. It is not the KBRA rating. It shows the same hunger for capital before the exchange.

BB+ is not a verdict. It is a rung. Below it, junk. Above it, investment grade. Between them, an AI lab that keeps debt off its own balance sheet and puts it on chips, SPVs and yields of 8.5%.

Image: Sharon Hahn Darlin, Salesforce Tower, San Francisco, 16 April 2022, CC BY 2.0, Wikimedia Commons. The photograph is of the skyline, not Anthropic’s offices.

Sources consulted: Anthropic assigned highest junk credit rating in June — Financial Times; Anthropic finalising US$15 bil pre-IPO credit facility — Bloomberg.