Id-sources.json refers to the tech specification by IAB Tech Lab, specifically aimed at enabling digital businesses to declare particular user ID sources they’re working with. 

What is id-sources.json?

From the technical perspective, id-sources.json is a file that maps out all sources of user identifiers a particular digital business (e.g. a publisher, advertiser or agency) is utilizing. 

The file needs to be hosted in the root folder of a company’s ad domain, i.e. (please note, that the URL mentioned herein is just an example, so following it will yield no result), and be structured in a machine-readable format. 

What’s inside

The parent object in id-sources.json includes several required elements, including the object array sources, as well as the version of the specification, and the information regarding the last update. 

Meanwhile, the object sources enlists all sources of user IDs and their attributes, including the source, name, transformation and the transformation_methods, with the latter being required only in case the transformation parameter value is true.

Potential Benefits

One of the key benefits of the newly-introduced IAB Tech Lab’s specification is that it provides businesses with a standard, i.e. unified and transparent way to declare ID sources they’re using. 

This allows a better understanding of what provider supplies a particular data segment/s, and who is utilizing which of those data segments, hence helping to improve the overall transparency of the supply chain in programmatic video advertising.

Perspectives of Adoption

Given that the id-sources.json specification was only released for a public comment in October 2021, the prospects of its market-wide implementation in 2022 are still vague. However, its adoption can accelerate in Q2 – Q4 2021, for instance, in case industry leaders opt for enforcing it among their Supply and Demand partners. 

For more information about id-sources.json, please refer to the AdPlayer.Pro’s implementation guide.

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