It's unlikely that aliens, if they're out there will have any reason to beam a signal to every planet in existence. It would not be our earth alone because they would have no idea who or what is here because of the enormous distances and how long it would take to observe any planet tens, hundreds and thousands of light years away.
Any message sent by them or us would have to be a tightly aimed beam of energy because any signal that comes out of this or any planet will be soon degraded to the point where it wouldn't be distinguishable from cosmic background noise.