{"slug": "anthropic-restores-fable-5-after-export-controls-lifted", "title": "Anthropic restores Fable 5 after export controls lifted", "summary": "Anthropic restored its Fable 5 AI model to all deployment channels on July 1 after the US Commerce Department lifted export controls that had been imposed on June 12. The controls were triggered by a researcher's report that Fable 5 could identify software vulnerabilities and produce exploit code, but Anthropic deployed a classifier blocking the technique in over 99% of cases. The company noted that multiple weaker models, including Opus 4.8, GPT-5.5, and Kimi K2.7, could reproduce the same behavior.", "body_md": "US Commerce lifted export controls on Claude Fable 5 and Mythos 5 on June 30, and Fable 5 returned to Claude.ai, Claude Platform, Claude Code, and Claude Cowork on July 1, ending an 18-day suspension following a June 12 Commerce directive. The controls were triggered by an Amazon researcher report describing a prompting technique that led Fable 5 to identify software vulnerabilities and produce exploit demonstration code. Anthropic trained a new classifier blocking that specific technique in over 99% of cases; blocked requests are rerouted to Opus 4.8 with a user notification, at the cost of more false positives on routine coding tasks. CAISI reviewed the safeguards before Commerce withdrew controls. Critically, Anthropic confirmed that multiple weaker models - including Opus 4.8, GPT-5.5, and Kimi K2.7 - could reproduce the same vulnerability-identification behavior, and every model tested could produce the same exploit demonstration code. For practitioners: a jailbreak Anthropic classifies as 'minor' (safety margin intrusion, not a core dangerous-capability breach) was sufficient to trigger policy action affecting all deployment channels.", "url": "https://wpnews.pro/news/anthropic-restores-fable-5-after-export-controls-lifted", "canonical_source": "https://letsdatascience.com/news/anthropic-restores-fable-5-after-export-controls-lifted-9f6f51ce", "published_at": "2026-07-01 11:30:51+00:00", "updated_at": "2026-07-01 14:56:51.099849+00:00", "lang": "en", "topics": ["ai-safety", "ai-policy", "large-language-models", "ai-agents"], "entities": ["Anthropic", "Claude Fable 5", "Mythos 5", "Opus 4.8", "GPT-5.5", "Kimi K2.7", "US Commerce Department", "CAISI"], "alternates": {"html": "https://wpnews.pro/news/anthropic-restores-fable-5-after-export-controls-lifted", "markdown": "https://wpnews.pro/news/anthropic-restores-fable-5-after-export-controls-lifted.md", "text": "https://wpnews.pro/news/anthropic-restores-fable-5-after-export-controls-lifted.txt", "jsonld": "https://wpnews.pro/news/anthropic-restores-fable-5-after-export-controls-lifted.jsonld"}}