Data Clean Rooms and the age of the aspiring walled garden

Increased regulation and changes in the data privacy landscape are creating new challenges for brands, agencies and advertisers, which is driving up the prominence of data clean rooms.


Data clean room technology helps publishers and content platforms keep their first person user data private when brands and agencies advertise their products and services on those platforms

Here, Vlad Stesin, co-founder and CSO of data collaboration and clean room company, Optable, explains why advertisers should be looking into the technology amid the rise of so-called walled gardens on the web.

No-one with an interest in digital media can have missed the increasing prevalence of the walled garden.


According to eMarketer, at least 70% of digital ad spending goes to Google, Facebook and Amazon, the three most prominent walled-gardeners, while numerous relatively smaller publishers are also encircling their assets and commodifying their rich data in all manner of ways.


Large or comparatively small, there are two main components to a modern media walled garden: quality owned and operated inventory on the one hand, and quality consented audience data on the other.


A modern walled garden in possession of assets like these will not, of course, sell this data or frivolously offer direct access to its inventory to a third party.


Instead, it will do everything it can to protect access to that inventory and maintain its premium quality – although, in some cases, lesser inventory with little or no data may be funnelled through other distribution channels, such as ad exchanges.


The appeal of independence


Today’s advertisers – whether that means brands with in-housed media departments or just the traditional agency representatives – have to contend with the rising number of walled gardens and the complexity of managing the fragmentation they create.


In many ways, the situation marks a return to the pre-programmatic era, when it was extremely hard to achieve scale for quality targeted inventory, and holistic measurement – even simple reach and frequency reporting, let alone cross-publisher attribution – was, like now, increasingly hard to come by. Just talk to the folks who plan CTV campaigns across multiple CTV publishers.


Most of the time they have to fly blind – the only way to get representative results is by spending as much as possible with a single publisher.

In a context like this, it is clear that the reason we hear so much about data clean rooms is only partly because of the deprecation of cookies and MAIDs – although those are clearly important facts of life right now.


But it’s also because, as we have discussed, more and more operators are building their own walled gardens.


To a degree, this building spree has been precipitated by technological and legislative changes related to privacy. But more importantly, it is a reflection of the commercial opportunity that stems from independence and the ability to determine your own destiny.


Walled gardens are here to stay – how should advertisers engage?


And if this sprawling neighbourhood of well-defended data havens is to work for both advertisers and data owners, walled gardens must enable data matching for activation and measurement.


As a result of years of experimentation, established, dominant walled gardens have already realised this and made the necessary accommodations.


From now on, and into the future, all aspiring walled gardens will need to do the same, and data clean rooms (DCRs) are one of the ways they will do it.

We’re still in the infancy of the evolution of DCRs. However, ultimately privacy-enhancing technologies (PETs) implemented by DCRs offer solutions to a range of problems that stem from the fragmentation created by the boom in wall gardens.


As standards such as IAB’s OPJA (Open Private Join & Activation) specification keep evolving and adapting to more and more use cases, a part of the ecosystem will be rebuilt into a new liquid market of addressable and measurable inventory.


The importance of the data clean room approach for aspiring walled gardens is now evident.


DCRs provides ways to securely plan, activate and measure ad campaigns without sacrificing a publisher’s independence, and without jeopardising user privacy by donating data to third parties.


The age of the walled garden is well and truly upon us, and the data is no longer solely in the hands of the tech giants.


All that remains for advertisers and publishers is to make this world work for them.



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