3 – 9 August 2026

At 07:05 UTC on August 5, Anthropic said it had identified the cause of elevated error rates on requests to Claude Mythos 5, Claude Fable 5, and Claude Opus 5, and that a fix was in progress. The status page lists claude.ai, the Claude API, Claude Code, and Claude Cowork as affected, with no recovery note posted as of publication.

The same three models, along with Claude Haiku 4.5, went down on July 25. That episode ran 1 hour and 4 minutes, from 18:40 to 19:44. A day before this one, on August 4, the status page logged a separate major outage with errors across many models plus a minor incident on Claude Sonnet 5.

‌Fable 5 now runs on usage credits for Pro and standard Team seats

As of July 20, 2026, working with Claude Fable 5 on Pro plans and standard Team seats is billed through usage credits. The extended free access on paid plans ran out on July 19.

Max and Team Premium subscribers still get Fable 5 included, capped at 50% of their limits. Anthropic handed Pro and Team Standard users a one-time $100 credit.

Anthropic has retuned the biology safeguards in Claude Fable 5. In the company's own testing, refusals on biological queries fell roughly 85% across all of its products, and the model now answers a wider range of everyday health and educational questions.

What Anthropic classifies as dual-use still gets handed off to Opus 5: virology, toxicology, molecular design. That leaves Fable 5 unsuitable for professional biology research and drug development, a gap Anthropic says it plans to close through trusted access channels.

In late July, former Anthropic engineer Adi Baradwaj publicly accused the company of the opposite: watering down safeguards to win corporate contracts.

Researchers at Stanford have published a public collection of more than 1,000 system prompts scraped from applications built on ChatGPT, Claude and other large language models.

The dataset accompanies AISPA, a paper proposing a method for auditing those prompts from the user's side. Erik Brynjolfsson and Alex Pentland are among the authors.

The preprint is on arXiv as 2607.28617, 2026.

Dario Amodei is concerned that some employees come to Anthropic for the money rather than the mission, Axios reports. He's said it as Anthropic, OpenAI, and other labs fight over the same pool of researchers, and he's refusing to bump salaries in response to poaching.

Mission Local previously reported on an Anthropic job listing with a base salary of $65,000 to $85,000, which set off an argument over how much the company actually pays technical staff.