Anthropic launches Claude Fable 5.2 and Mythos 5.2 models

New models and pricing

Anthropic is announcing two new models: Claude Fable 5.2 and Claude Mythos 5.2, which it says are designed to take on "daunting" technical challenges. The company claims the new models show improvements in coding, reasoning, and vision, and can generate outputs faster than the 5.1 versions of the Fable and Mythos models.

The models are priced at $8 per million tokens of input and $40 per million tokens of output, roughly 20% below the 5.1 generation, according to CNBC. An optional fast mode, which speeds up token generation by up to 2.5 times, costs $16 per million input tokens and $80 per million output tokens, Anthropic said.

Availability and capabilities

Claude Fable 5.2 is available on all platforms, including Amazon Web Services, Google Cloud and Microsoft Azure, the company said. Claude Mythos 5.2 is the same underlying model without certain cybersecurity and biology safeguards. Organizations can apply for access through Anthropic's Cyber Verification Program and Life Sciences Verification Program.

Anthropic said both models scored higher than Claude Opus 5.5 on almost all the capabilities it evaluated. On the FrontierCode 2.0 coding evaluation, Fable 5.2 scored 49.1% at Xhigh effort, compared with 45.5% for Opus 5.5 and 32.4% for Fable 5.1.

The company said it ran prerelease safety testing, and that external evaluators including the U.K. AI Security Institute and METR tested the underlying model. In early testing, Fable 5.2's safeguards blocked about 55% fewer requests than Fable 5.1's, Anthropic said.

IPO and company context

The launch comes as Anthropic prepares for an initial public offering that could happen as early as next week, according to CNBC. Anthropic is targeting a valuation between $1 trillion and $1.5 trillion, a step down from the $2 trillion figure that had been floated in recent months. Anthropic disclosed in an amended prospectus that its revenue came to $33.24 billion over the nine months through Sept. 30, an increase of about 1,200% over the year-earlier period.

Why it matters

• Anthropic is expanding its frontier model lineup with faster, cheaper pricing than the 5.1 generation.
• Mythos 5.2 removes certain cybersecurity and biology safeguards and is restricted to vetted organizations.
• The release precedes a potential IPO with a targeted valuation of $1 trillion to $1.5 trillion.

Sources

• qz.com: Anthropic releases two new Claude models and cuts prices 20%
• theverge.com: Anthropic launches new Claude Fable and Mythos 5.2 models | The Verge

This article was drafted with AI assistance and checked against the sources above. Company claims are reported as claims. Cover image is AI-generated.