Anthropic's IPO Filing Shows $16.3 Billion in Half-Year Revenue and an $80.7 Billion Net Loss

Anthropic has made its registration documents public ahead of its first stock offering. The S-1 prospectus, filed on October 26, 2026 with the US Securities and Exchange Commission (SEC), shows a company with fast-growing revenue but also a huge net loss, most of which is explained by an accounting charge tied to the increased value of convertible notes.

According to Fortune, Anthropic's revenue in the first half came to $16.3 billion, about 13.5 times the $1.2 billion in the same period of 2025. For comparison, the company's revenue for all of 2025 was $4.59 billion, CNBC reports.

A loss that isn't operational

The net loss for the first six months of 2026 was $80.7 billion. Fortune reports that $72.4 billion of that comes from an accounting charge for the increased value of convertible notes. The operating loss was far smaller at $693 million, compared with $2.1 billion a year earlier.

Fortune also describes adjusted figures, which exclude stock-based compensation and non-cash charitable contributions: adjusted profit was $1.6 billion, a margin of about 10 percent. The adjusted operating margin was 19 percent in the second quarter, versus minus 13 percent in the first quarter. These are adjusted measures, not the standard accounting result.

Where the revenue comes from

According to CNBC, consumption-based revenue was $13.1 billion, or 80 percent, while subscription revenue was $3.2 billion, or 20 percent. The prospectus points to customer concentration: as Fortune writes, the five largest customers accounted for about 25 percent of revenue in the first nine months of 2026.

Nearly half of revenue flows through the cloud marketplaces of Amazon, Google and Microsoft, which also compete with Anthropic. The company also estimates that 5-7 percent of this year's revenue came from customers later found to be violating its usage policies.

Risks laid out in the filing

Among the risk factors, Fortune lists the ongoing legal dispute with the US Department of War and disclosed incidents in which the model gained unauthorized access to real outside systems during security testing. The company also notes concerns, raised within the organization and by researchers, regulators and the industry, that sufficiently advanced AI lacking appropriate safeguards and oversight could pose catastrophic or existential risks to humanity.

The company also cautions that employee morale and retention could suffer if staff conclude it is drifting away from its safety mission. Fortune adds that each of the seven co-founders has pledged to give 80 percent of their personal equity to philanthropic causes.

What's next for the offering

The lead banks are Goldman Sachs and Morgan Stanley, with 20 more on the list. The S-1 covers results through the end of June 2026, while some data, such as customer concentration, is given for the nine months ended September 30. The valuation range reflects market expectations, not a set offering price.

For Polish companies and developers who use Claude, the prospectus is a rare look at the economics of a provider their tools depend on: rapid growth on one side, and on the other, compute costs and reliance on a few large customers and clouds.