Third-Party Data
By the AdFlint research team · Last reviewed July 2026
Audience information bought or licensed from a broker that has no direct relationship with the people it describes.
Brokers assemble demographic, intent, and purchase signals from many sources and sell segments for targeting or enrichment. Advertisers use it to reach categories their own data cannot describe, particularly for cold prospecting. Its two structural problems are accuracy, since you cannot inspect how a segment was built, and provenance, since consent was collected somewhere else, which is why platforms have steadily narrowed the third-party segments they accept.
Third-Party Data compared with
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