If communication involves some transactions cost to both sender and recipient, what policy ensures that correct messages - those with positive social surplus - get sent? Filters block messages that harm recipients but benefit senders by more than transactions costs. Taxes can block positive...

We investigate welfare effects of mechanisms designed to improve total communications value. Identifying first contact information asymmetry and negative externalities as the critical problems, we analyze best-in-class solutions from law, technology, and economics. Comparison leads to several...