’s sellers.json file’s  ( Formerly StartApp) sellers.json file is now live and accessible to all partners, including publishers, ad exchanges, ad networks and demand-side platforms (DSPs). Sellers.json is a step forward in programmatic transparency. With it in place, advertisers get transparency and clarity on everyone involved in every programmatic transaction.

What is sellers.json

Following up on the digital industry’s transparency and quality goals, IAB has developed sellers.json. Sellers.json is a data file containing identifying information about publishers’ accounts within their advertising platforms. It’s a digital identifier of the supplier.

The file functions similarly to an app-ads.txt file, providing a transparent record of all media buys. This data file is improving supply chain transparency within RTB and programmatic buying as an advertiser can clearly identify the supplier. It also allows media buyers to see all intermediary parties of every bid request.

why is sellers.Json beneficial 

It’s a critical improvement on the sell side as well. Since sellers.json files are publicly accessible, app publishers and developers can use them to gain additional transparency and see if any unauthorized parties are reselling their inventory. It also can be used to make sure that any supply-side platforms (SSPs) are being honest about who they’re actually working with within the wider ecosystem.

For more information about sellers.json visit

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