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IAB Tech Lab Releases New Buy-side Transparency Specifications for Public Comment

Buyers.json and DemandChain Object Enable Sellers to Know Their Advertisers, to Prevent Malware and Ensure Brand Safety and Ad Quality

NEW YORK – March 30, 2021 – IAB Tech Lab, the digital advertising technical standards-setting body, released today buyers.json and DemandChain Object specifications for a 30-day public comment period, which begins today and lasts until April 30, 2021. Over the past several years, Tech Lab has developed technology standards and best practices to provide transparency and brand safety from sellers to buyers, including ads.txt (Authorized Digital Sellers, for publishers to declare who sells their inventory) and sellers.json (for supply-side platforms / exchanges to declare their sell-side relationships). Now, buyers.json and DemandChain Object provide similar attributes about buyers, mirroring the structure of sellers.json and SupplyChain Object, which were unveiled in July 2019.

As part of a broader effort to eliminate malvertising and other ad quality issues from the digital advertising ecosystem, these buy-side transparency specifications enable sellers to identify who is buying their inventory. buyers.json enables advertising systems to publicly declare the buyers they represent, and DemandChain Object provides transparency around every entity involved in a specific transaction. Armed with this information, publishers and supply-side platforms (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. This also aims to help publishers better monitor spend on their inventory and ultimately their audiences.

“Lack of transparency into buyer identity is a critical problem for sellers to ensure that advertising is brand safe and malware-free,” said Amit Shetty, Vice President, Programmatic Standards and Partnerships, IAB Tech Lab. “buyers.json and DemandChain Object will provide the transparency we need for the sell-side to work together with the buy-side to keep consumers safe.”

“buyers.json and DemandChain Object provide publishers and their tech partners with much-needed transparency equivalent to that provided by sellers.json and SupplyChain Object for buyers,” added John Clyman, Vice President, Engineering, Marketplace Quality & Security at Magnite. “Widespread adoption of these standards will enable the industry to better combat malvertising and nefarious behavior, and is a critical factor enabling publishers to more confidently monetize their inventory while preserving positive user experiences, promoting continued growth in programmatic transactions.”

To review the proposed standard and provide feedback, please go to: 

About IAB Technology Laboratory 

Established in 2014, the IAB Technology Laboratory (Tech Lab) is a non-profit consortium that engages a member community globally to develop foundational technology and standards that enable growth and trust in the digital media ecosystem. Comprised of digital publishers, ad technology firms, agencies, marketers, and other member companies, IAB Tech Lab focuses on solutions for brand safety and ad fraud; identity, data, and consumer privacy; ad experiences and measurement; and programmatic effectiveness. Its work includes the OpenRTB real-time bidding protocol, ads.txt anti-fraud specification, Open Measurement SDK for viewability and verification, VAST video specification, and Project Rearc initiative for privacy-centric addressability. Board members/companies are listed at:
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IAB Tech Lab Media Contact
Kate Tumino / Brittany Tibaldi
212-896-1252 / 347-487-6794 /