Anthropic’s growth slowed and costs jumped in the third quarter, updated IPO filing shows

Anthropic's financial growth slowed in the third quarter of 2026, as revealed in an amended IPO prospectus published on Monday by the U.S. Securities and Exchange Commission. The third quarter saw revenue of $17 billion, up from $11.6 billion in the second quarter and $1.4 billion a year earlier. Despite still experiencing rapid sales growth, the rate of growth has decelerated, with a 47% increase compared to the prior quarter.

However, this growth came with increased operational costs, resulting in an operating loss of $567 million for the quarter, up from a $974 million profit in the previous quarter. This loss was primarily due to the company's reliance on short-term compute commitments which are more expensive than its multi-year contracts. Additionally, the company reported $2 billion in non-cash charges related to an employee donation matching program.

Stripping out stock-based pay and charitable charges, Anthropic's business remains profitable on an adjusted basis, although its adjusted operating margins have shrunk to 15%, down from 19% in the second quarter. The high costs of short-term compute may also compel Anthropic to seek long-term data center capacity. The filing revealed a planned $895.4 billion spending commitment, predominantly for compute and infrastructure.

A significant portion of this is dedicated to Anthropic Direct, its own dedicated infrastructure. The company also mentioned pricing pressure from competitors reducing AI model prices to attract customers, which partly offset the growth in revenue from increased usage. Despite reporting a net loss of $23.3 billion for the quarter, the loss was largely due to an accounting charge related to the increasing value of its convertible notes.