The $72B number is just for convertible notes sold prior and through 1st half of 2026. They were issued as a way to finance growth costs (e.g. acquiring compute).

There might be some additional sold in Q3, but that wasn't published here. But these notes aren't costs that Anthropic has to pay in any normal sense - they're shares they sold pre-IPO and valued at $72B. Anthropic would have to pay that much to buy them back at said valuation price, but they're not obligated in any way to do that.

Post IPO, they'll have alternative avenues for sourcing funds... (e.g. secondary offerings, corporate bonds). Continued growth at this rate will need continued financing, but it wouldn't be done using convertible notes.

The real liabilities are the hundreds of billions in non-cancelable compute costs Anthropic owes Google, Amazon etc, over the course of the next 10 years.