How can you tell that the leads (contacts) added to your database are legit? Will there be any team that will check the added contacts for validity?
Since we already hold plenty of data we will coressrefence profiles mainly updating them and when some inconsistency found that would raise a flag.
Also, our chrome plugin which would work as a data transmitter would pick up only certain structured data which we consider legit.
Still, some manual verification may be involved.
I raised the same issue in this topic several days ago. Some of the email that the extension finds do not exist. You should take extra care to solve this.