Seller Defined Audiences And Data Clean Rooms Will Solve The Identity Problem

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The Sell Sider” is a column written by the sell side of the digital media community.


Today’s column is written by Vlad Stesin, chief strategy officer and co-founder of Optable


The erosion of third-party cookies and the fragmentation of identity have compelled publishers to invest in reviewing and rebuilding their first-party data strategies. As a result, there is now a tremendous amount of quality first-party data that can be safely surfaced to brands.


That’s one reason why the IAB Tech Lab’s Self-Defined Audiences (SDA) standard – a superior rival to Google’s Topics API as ​a proposal for interest-based advertising – may be one of the most significant standards to be published as we climb toward a workable set of post-cookie digital advertising solutions.


SDA allows individual publishers to develop and scale anonymized first-party data sets for all digital environments, instead of relying on external systems to aggregate and normalize audience data points across their domains.


News Corp’s Steph Layser recently laid out the strengths of SDA very nicely, but the essence is this: SDA is privacy-centric, open, transparent and accountable. It keeps data where it was created. If advertisers want quality data, they can get it, optimized for quality rather than price, directly from the quality publisher who collected it.


If it works as well as it promises to, that’s good news for advertisers and publishers, but bad news for intermediaries who weren’t adding value. Plus, it’s a welcome challenge to the all-powerful platform solutions.


Navigating tension between publishers and advertisers


No solution is ever simple or above argument. SDA has been well received by publishers who think it could help them grow their ad revenue significantly, but some advertisers worry it could allow publishers to inflate their audiences.


In practice, publishers and data providers label their data quality according to the preexisting Data Transparency Standard spec to inform buying decisions at scale. They also submit to a voluntary annual audit of their data label contents.


SDA potentially eliminates marketers’ need to work with contextual ad companies, as it supports contextual and content signaling by conveying content taxonomy IDs and integrating with proprietary content labeling services.


But perhaps the most appealing aspect of SDA, as it shifts data execution from the buy side to the sell side, is its potential to resolve some of the lingering distrust in the supply chain, whether between buyers and sellers or advertisers and consumers.


“SDA … prioritizes the first-party relationship between publishers and consumers – and not just a random collection of tags and pixels someone jammed into the HTML,” Steph Layser wrote.


Publishers are rightfully regaining their power and have a real opportunity to create better privacy-conscious experiences for brands. SDA is a great mechanism to enable that.


Data clean rooms bring SDA to life

For publishers, SDA is a way to surface audience data, but it still requires certain infrastructure to facilitate the process. That is where data clean rooms come in.

  • Data clean rooms use SDA and Prebid to signal overlapping audiences to advertiser DSPs. This minimizes data movement and forgoes the need for advertisers to track and stitch users across publisher sites.
  • SDA enables the addressability of matched audiences at scale, as cohorts, across many publishers. Audiences matched through clean rooms are activated using publisher first-party data and signaled using SDA. Advertisers can easily target the resulting cohort across publisher domains, without needing to see actual identifiers.


As panic surrounding a cookieless future persists, it is heartening to look out on industry-driven efforts like this. Seller defined audiences fulfill all the necessary criteria of the post-cookie targeting solution, while also righting some of the structural wrongs that have placed Big Tech platforms in such an incontestable position of power.


Rightful data ownership


We’re starting to see a patchwork of solutions aimed at fixing the ecosystem: new standards, such as SDA, but also a new generation of CDPs and integrated data clean rooms that help tie it all together.


We can now see a future that doesn’t require a global identity graph and the audience data ownership that comes with it. In fact, the future holds quite the opposite. Data stays with the organization that earned it, information transfer is minimized and the purpose to which it can be put is limited, in the right way. 


We’re not there yet, but with SDA and the right collaborative tools, we’re on our way toward a better, privacy-preserving, media buying and selling workflow.


Also published in: Ad Exchanger

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