AI Newsletter

The British AI Security Institute tested Claude Mythos in a realistic attack simulation – with alarming results that UK Bank of England Chief Bailey classified as a 'major cybersecurity risk'. Unlike the previously reported zero-day discovery, this involves state-authorized red-team tests that evaluate the model's offensive potential under controlled conditions. This signals that regulators view Mythos not just as a product risk, but as a national security issue.

With nearly 3,000 upvotes and 411 comments, the community debate explodes: BridgeBench data shows that Anthropic systematically weakens models after release – while simultaneously announcing Opus 4.7 for this week. Users accuse Anthropic of misusing benchmarks as a marketing tool, as actual model performance measurably declines months after release. The loss of trust hits Anthropic precisely when the company is at the peak of its hype with Mythos and $800-billion valuation rumors.

OpenAI has rolled out GPT-5.4-Cyber in a limited test – explicitly positioned as a competitor product to Claude Mythos in the cybersecurity segment. The move comes after a leaked CRO memo internally acknowledged that Anthropic has 'exceeded every projection' in the enterprise sector. Polymarkets with $8 million volume still see Anthropic at 92% for the best model by end of April – OpenAI comes in at only 3%.

Private AI companies raised more capital in Q1 2026 than in all of 2025 – OpenAI's $122-billion round alone accounts for 54% of it. Even without this mega-deal, $104 billion would be a historic record. In parallel, OpenAI IPO market cap expectations on Polymarket rise above $1 trillion (59% probability, +24% this month) – capital inflow to the industry is accelerating structurally.

Mistral unveiled the 'Forge' platform at Nvidia GTC, enabling companies to build their own AI models based on Mistral – as direct counter-positioning to OpenAI and Anthropic in the enterprise market. The strategy bets on customization and data control rather than competing in the model leaderboard race. Given the dominance of Chinese open-source models in Silicon Valley and growing regulatory concerns, the European approach could gain strategic significance for sovereignty-conscious enterprise customers.