[10/23 00:00 UTC] Anthropic uses Claude to mathematically prove security properties in 123 op…

AI News Flash for October 23, 2026 at 00:00 UTC. Topics: 1. Anthropic uses Claude to mathematically prove security properties in 123 open-source libraries, uncovering bugs that slipped past trillions of tests https://www.anthropic.com/research/formal-verification 2. Etsy bans AI-generated recipes and patterns and requires real photos of items https://www.cnbc.com/2026/10/22/etsy-bans-ai-generated-recipes-patterns-from-its-online-marketplace.html 3. A federal appeals court removes a judge whose orders contained AI errors from a Mississippi anti-DEI case https://www.reuters.com/legal/government/appeals-court-lifts-block-mississippis-dei-ban-ejects-judge-over-ai-errors-2026-10-22/ 4. The Agentic AI Foundation takes in four new projects from OpenAI, Anthropic, Hugging Face and Alibaba https://siliconangle.com/2026/10/22/agentic-ai-foundation-adds-four-more-open-source-ai-tools/ 5. Rivian buys UK startup Third Dimension to turn real-world driving data into 3D simulations https://techcrunch.com/2026/10/22/rivian-buys-world-model-startup-to-accelerate-self-driving-ambitions/