Anthropic ships Claude Fable 5.2 and Mythos 5.2 as its IPO looms

Anthropic dropped two new models Monday: Claude Fable 5.2 and Claude Mythos 5.2. The company says they spit out answers 30% faster than the previous generation and cost 20% less than the 5.1 models. Pricing lands at $8 per million input tokens and $40 per million output tokens.

The timing is no accident. Anthropic is prepping an IPO roadshow and could go public as soon as next week, and it's chasing a valuation of $1 trillion to $1.5 trillion — down from the $2 trillion figure that had been floated in recent months, according to CNBC. The company's amended prospectus showed $33.24 billion in revenue for the nine months ended Sept. 30, up roughly 1,200% from a year earlier.

These are Anthropic's first frontier models since CEO Dario Amodei called for the industry to slow the pace of AI development in September. The company says the new releases went through rigorous safety and alignment testing, backed by new evaluations and post-launch monitoring tools. Not a pause, according to Dianne Penn, Anthropic's head of product management for research: “We called for pacing, not pausing,” she told CNBC.

Both models have history. Mythos arrived in April with a limited rollout to a select group of organizations because of its advanced cybersecurity chops. Fable followed two months later as a publicly available version of Mythos with extra safeguards baked in. The pair helped drive Anthropic's explosive year and drew attention from Wall Street and government officials alike.

Penn pitched Fable 5.2 at “power users or power use cases” — complex, open-ended technical work in engineering, mathematics and robotics. Claude Opus 5.5, released in September, is the better pick for everyday tasks, she said, though that gap could narrow. “These are just net new things that are completely novel, and so they're frontier use cases,” Penn said. “We expect that over time to maybe trickle to the Opus class.” Fable 5.2 is generally available now; Mythos 5.2 goes only to vetted organizations through Anthropic's Life Sciences and Cyber Verification Programs.