Simon Willison — 2026-06-16#
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The meatiest topic today is Simon’s sharp criticism of the export controls placed on Claude Fable 5. He connects the dots between a press report and security expert Katie Moussouris to point out the absurdity of penalizing an AI model for successfully fixing security vulnerabilities, which is a core feature of cyberdefense.
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The Fable 5 Export Controls Harm US Cyber Defense Simon strongly criticizes the US export controls placed on Claude Fable 5, citing security expert Katie Moussouris. The so-called “jailbreak” that triggered the ban was merely researchers asking the model to “fix this code” after it had refused a prompt to “review the code for security issues”. Simon argues that banning models for executing the “find, fix, and test loop” fundamentally misunderstands how AI assists in defensive security, effectively penalizing a model for fixing bugs.