Data Aggregator

A data aggregator is an organization that collects and compiles data from various sources, often offering results or access for resale. There are three primary types of data aggregators:

Offline Data Aggregators
Generally establishing an interest in managing data from sources prior to the proliferation of the internet, companies like Acxiom and ChoicePoint have offered data acquired through both public record and private sources (like customer loyalty cards) for sale. This data is primarily sold to advertisers at the ZIP or ZIP+4 level, in order to maintain anonymity. Increasingly, the offline data is migrated for use in online campaign targeting.
Online Data Aggregators
Most often called Data Management Platforms (DMPs), companies like Lotame and BlueKai establish relationships with a large number of websites in order to gain a big-picture view of cookied users that would be inaccessible to individual sites.
Personal Data Aggregators
Used primarily for either investigation of an individual or reputation management, companies like Spokeo and allow information for an individual to be collected in one place. This has little use for digital advertising.