Third-Party Data
AnalyticsAlso: 3P Data · Purchased Data · Data Broker Data
Quick definition
Third-party data is audience information collected by external companies and sold or licensed to advertisers. It includes demographics, interests and browsing behaviour gathered from sources you don't control.
Where it shows up in the data
What it actually means
Third-party data refers to audience information that you buy or license from someone else — companies whose business model is collecting and reselling data. This includes demographic profiles, purchase intent signals, interest categories and browser behaviour tracked across the web using third-party cookies. For years it underpinned most digital advertising targeting, allowing advertisers to reach people based on behaviours observed across thousands of websites, not just their own. The problem is reliability, compliance and the structural shift away from third-party cookies. Apple's Intelligent Tracking Prevention, Firefox's total cookie protection and Chrome's upcoming third-party cookie deprecation are systematically dismantling the infrastructure this data runs on.
Third-party data was the rental property of advertising. First-party data is the house you own.
The Australian context
Australia's Privacy Act 1988, particularly the Privacy Amendment (Enhancing Privacy Protection) Act and proposed reforms, tightens the conditions under which third-party data can be used for targeting. The Australian Digital Advertising Alliance (ADAA) also has frameworks for consent that apply to third-party data use in programmatic advertising.
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New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.
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