Right now, "Stale" means bugs untouched in the last 180 days.

That said, we've heard feedback that this is arbitrary and isn't really helpful, so in the new version of Chromium Dash we're prepping now, we've actually removed the "Stale" category entirely.  You can see this in action here: https://chromiumdash-staging.googleplex.com/components (it'll take forever to load, but it'll get there - note the bug counts are fake in the staging instance as well).

Given this, I'm going to mark this as Fixed but please re-open if you have more questions, or if you don't like the new interface.

Thanks for the response.

My first thought was that it was aligned with SheriffBot (365 days), but that theory didn't match the numbers. Remove Stale does sounds like the best way forward.