Anthropic’s ad bill is soaring, according to IPO filing

Anthropic's forthcoming IPO filing reveals a significant surge in ad spending associated with its AI product, Claude. The company's advertising budget has grown from $33 million in 2024 to $147 million in 2025, surpassing the combined sales and marketing expenses of Duolingo, a marketing-focused app, in 2025. The increase continued in the first half of 2026, with marketing and advertising costs rising by an additional $273 million compared to the previous six months.

Despite the substantial rise, the ad budget remains a small fraction of Anthropic's total expenses, which amounted to $3.17 billion in the first half of 2026. The majority of this expenditure was directed towards cloud companies that resell Claude's services, with Claude's fees accounting for $2.7 billion of this increase.