Will there be a second breach of Mythos announced by EOM May 2026?

Question

“We’re investigating a report claiming unauthorized access to Claude Mythos Preview through one of our third-party vendor environments,” an Anthropic spokesperson told TechCrunch. The company said that, so far, it has found no evidence that the supposedly unauthorized activity has impacted Anthropic’s systems in any way.

The group in question is “interested in playing around with new models, not wreaking havoc with them,” the source told the outlet.

Articles

https://techcrunch.com/2026/04/21/unauthorized-group-has-gained-access-to-anthropics-exclusive-cyber-tool-mythos-report-claims/

https://www.bloomberg.com/news/articles/2026-04-21/anthropic-s-mythos-model-is-being-accessed-by-unauthorized-users

Manifold Markets · Answer

Probably not — Manifold Markets prediction market estimates a 38% chance (5 traders, as of Apr 22, 2026).