DMP

A data management platform (DMP) is software that collects first-party, second-party and third-party audience data, sorts it into segments, and sends those segments to buying and selling platforms for ad targeting.

The UK CMA describes DMPs as services that import data, manage or enrich it, and send it back out, mainly to improve audience targeting. Advertisers, DSPs, SSPs and publishers use them to combine their own data with third-party data and build audiences (CMA, Appendix M, paragraph 117, 1 July 2020).

Classic DMPs run on cookies and mobile advertising IDs. A user visits a site, a tag sets a cookie, and the DMP files that cookie into segments such as "in-market for a car". To use a segment in a campaign, the DMP syncs its cookie IDs with a DSP or SSP so both recognise the same browser. The data are usually pseudonymous and short-lived.

That design explains why DMPs lost ground. Several browsers block third-party cookies by default. Google kept third-party cookies in Chrome in April 2025 (Google, 22 April 2025), so cookie-based segments still work there. Elsewhere their reach keeps shrinking, and many buyers moved the work to customer data platforms, clean rooms and identifiers built from logins.

Example: A publisher's DMP finds that 40,000 visitors read three or more car reviews in a week. It labels them "auto intenders" and pushes the segment to the publisher's SSP. A car brand then buys that segment through a private marketplace deal at a higher CPM than the open auction pays.

Related terms: CDP, clean room, cookie sync, third-party data, DSP.

Authoritative source: UK CMA, market study Appendix M, paragraph 117 (1 July 2020).