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How Publishers and Advertisers Can Activate Sell-Side Targeting

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By Susan Wu, Senior Director, Marketing Research
February 8, 2023

The digital advertising industry has long had an imbalance of power between Big Tech and its walled gardens, and publishers and their ad inventory.

Now, however, the balance is starting to shift as third-party cookies fade away and sellers like publishers and retailers find themselves in a prime position to capitalize with tactics like sell-side targeting.

Here’s how publishers and advertisers should prepare for the coming sea change:


Sell-side targeting enables publishers to monetize even more inventory, but, first, they must do two things to appeal to advertisers.

For starters, they must make it as easy as possible for brands to advertise. That means both having access to different IDs, as well as using addressability technology that enables interoperability and experimentation so brands can test and learn as their campaigns roll out.

Next, publishers must enable standardization. As media buyers activate against multiple signals, publishers have an opportunity to—and indeed should—develop new standards for enhanced interoperability, as well as performance.


Meanwhile, sell-side targeting can deliver inventory and data that meets advertiser demand with greater scale, precision and effectiveness. Because this workflow aligns audience and inventory strategies, it’s the sellers that will now have the best knowledge of the audience, and therefore how to target it, especially with the deprecation of the third-party cookie.

One of the most popular audience capabilities supported through sell-side targeting is seller-defined audiences. Through seller-defined audiences, advertisers can segment users based on interest and purchase intent using the IAB Tech Lab’s audience taxonomy standard rather than PII or cookies. This allows marketers to access publishers’ first-party data in a privacy-friendly manner.

Other targeting capabilities enabled on the supply side that have gained buyer’s attention include ID solutions like first-party data matched to alternative IDs, modeled cohorts, but also non-ID solutions like contextual, and publisher first-party signals that can be transacted via a Deal ID. All of these tactics can increase operational efficiency for the advertiser.

It is critical that advertisers select the right sell-side targeting partner. We recommend looking for an SSP that offers a range of audiences, understands your KPIs, offers a value-add like supply-path optimization as initial steps, have privacy-safe and sustainable standards to future-proof your supply chain inventory.

For more on why sell-side targeting benefits publishers and advertisers, see this new guide produced in partnership with Digiday.