When we send sample data to a prospective client we are regularly pleased to hear that some of the contacts are already on the client’s subscriber lists. Why is this good? Because it shows that we are sourcing precisely the right type of B2B prospects for their requirements.
There is also contact data that the client already holds in unsubscribe lists (aka ‘suppression lists’) and together with subscriber lists are referred to as ‘exclusion lists’.
Obviously, though we don’t want to charge for data that the client already has.
So, how do we ensure that we do not send contact data to our clients that they already hold?