Anthropic’s Secret Mythos Model Leaks, Altman vs Amodei’s Decade-Long Feud, Anthropic Wins in Court

Today we’re covering the biggest AI stories of March 30th, 2026. Anthropic accidentally leaked details of its next flagship model called Claude Mythos through a CMS error — with the draft blog describing it as a new tier above Opus with cyber capabilities the company calls “far ahead of anything else available,” drawing comparisons to OpenAI’s own mysteriously timed pre-launch leaks. The WSJ published a deep dive into the decade-long personal feud between Sam Altman and Dario Amodei — tracing it back to a 2016 San Francisco group house, with leaked Slack messages, accusations of plotting, and comparisons to historical villains all painting a rivalry that’s about a lot more than just building better AI. Plus, Anthropic won a federal injunction blocking the Trump administration’s supply-chain-risk designation, with the judge calling it “classic illegal First Amendment retaliation,” and a community workflow from a son who used Claude to transcribe his late father’s handwritten letters and turn them into a family archive website.