This is indeed an account that originally belonged to an Guardian, namely @daveytea. But he no longer has access to it which he outlined in this post: [Discussion] Compromised Safe has allocated airdrop, how to solve?
The SAFE token is non-transferable for now, but changing the owners of a Safe is of course possible and makes such OTC deals quite straightforward. However, I recommend in this case to refrain from participating due to the Safe having been compromised.