One audience, cut the way you sell.
The brief is the specification, and it is written before the build. Rows that cannot be verified are separated from rows that failed verification. If a requirement had no countable equivalent, the nearest one is named.
Syntax screening
Removing malformed and obviously generated addresses before anything is paid to check them.
Format handover
Delivery in the structure your systems already accept, tested on a sample so nothing needs reworking afterwards.
Contact precedence
Choosing which person represents an organisation when several qualify, by a stated rule.
Describe the shape of the audience and we will come back with its size.