My best guess is that it means that the band still exists as a legal entity, for the purpose of collecting royalties etc. And that this leaves the door open for releasing old, as-yet-unreleased material (demos, alternate versions, etc.). But I don’t know much about the music business.
Aerosmith has been mentioned several times over in the “What one band is the epitome of classic rock for you” thread. If the question were restricted to American bands, I think they’d be a solid first choice.