Anthropic sued over Claude Max plans, alleging hidden usage caps

Karl Kahn filed a proposed class action against Anthropic on June 15 in the US District Court for the Northern District of California. The complaint targets the company’s $100 Max 5x and $200 Max 20x Claude subscription tiers and seeks refunds and damages for purchasers since the plans launched in April 2025.

Kahn says he upgraded to the Max 20x tier for intensive coding and encountered limits that made the advertised 20x boost unattainable. The filing describes a five-hour session that consumed roughly 15% of his weekly quota.

The complaint explains Anthropic measures usage in five-hour rolling windows while also applying a separate weekly cap. Kahn argues the combination of short-term windows and a weekly limit was not clearly disclosed and caused heavy sessions to be throttled sooner than the advertised multipliers suggested.

The suit asks the court to certify a class of all customers who purchased Max 5x or Max 20x since April 2025 and seeks refunds and damages under state consumer protection laws.

Anthropic added weekly caps in late August 2025 after power users ran Claude Code nearly continuously. The company said the change would affect fewer than 5% of subscribers and that caps reset every seven days.

Anthropic has argued that fixed-price “unlimited” tiers can lead to large losses because AI inference is costly, and that caps are a way to ration limited compute. Earlier reports described an enterprise client that incurred roughly a $500 million bill in one month.

A user quoted in the court filing wrote: ‘Now imagine what the Pro plan users face. But it helps us get better at prompting. And whenever I hit limits, I buy extra usage. Cost way less than Max.’

Anthropic declined to comment. The company is planning for a potential public listing and is involved in other legal disputes, including an ownership claim linked to an AI contract with the Trump administration.

The court will decide whether to certify a class and what remedies, if any, are appropriate. The filing opens the path to discovery and further proceedings.