buyers.json and DemandChain Object

buyers.json and DemandChain Object are two new buy-side transparency standards being introduced by the IAB Tech Lab (the 3rd being the Ad Product Taxonomy).  These standards help address the challenges around malvertising and nefarious ads, by providing transparency around the entities that are involved with publishing such ads.

The first, buyers.json, is a mechanism for advertising systems and other intermediaries between payor and publisher to publicly declare the buyers that they represent. Armed with this information, publishers and SSPs can more easily identify the sources of malvertising attacks, identify problematic buyers across multiple demand sources, and take appropriate action to protect themselves and their users.

The second, DemandChain Object, enables sellers to see all parties who are involved in buying the creative embedded in a given bid response. This extension object can be used with OpenRTB 2.x or OpenRTB 3.0.

In many ways, buyers.json and DemandChain Object can be considered the mirror images of sellers.json and SupplyChain Object, with the goal of providing similar level of transparency to publishers, just as sellers.json & SCO had provided transparency to buyers.

These specifications are published for public comment until April 30, 2021. Please provide your feedback by emailing or

Read the press release announcing the public comment release of buyers.json and DemandChain Object.

IAB Tech Lab Contact

Amit Shetty
VP, Programmatic & Partnerships