Mythos 6 has reportedly finished training — and Anthropic's last Mythos still isn't something you can call

The claim: Mythos 6 has completed internal training. It could eventually launch as Mythos 6 or Mythos 6.1. It is built to power the next generation of Anthropic's most capable systems. Deployment has reportedly been slowed by restrictions surrounding Fable 5 and Mythos 5. Any public release could come with regional limits, stricter access controls, or reduced capabilities compared to the internal version.

This one has a traceable origin, which puts it above most leak cards: it goes back to AI observer Andrew Curran, reporting that a model with capabilities beyond Mythos 5 has quietly finished training. Anthropic has not confirmed that the model exists.

Two details in the original are worth keeping, because they get sanded off in the retelling.

The version number is not settled. The same leak allows that it could ship as Mythos 5.1 rather than Mythos 6. Our board arms both patterns separately for that reason.

And the restriction claim is not speculation about a hypothetical policy — it describes something already true of the line. Mythos 5 exists and has never appeared in a public catalog; it is available to vetted partners only. Anthropic's own July 30 cyber-eval disclosure confirmed Mythos 5 in active internal use while it remained publicly unlistable. So "a more capable model that is trained but gated" is not a new pattern for Anthropic's top tier. It is the current pattern, and the leak is claiming it continues.

That has a practical consequence worth stating for anyone waiting on this. A Mythos-class model completing training does not imply you will be able to call it. The last one finished training, went into production use inside Anthropic, and is still not something you can buy.

Grade: rumor. Named observer, no first-party confirmation, and a version number the leak itself declines to commit to.