IAB Tech Lab Seeks to Unmask Programmatic Ad Supply Paths

The new standard expands the existing OpenRTB SupplyChain object—commonly known as schain—to track entities that handle bid requests without necessarily being part of the payment flow. By including technical custody, the update aims to illuminate the roles of infrastructure providers, such as ad servers, wrappers, and SDKs. According to IAB Tech Lab CEO Anthony Katsur, this change provides a more granular view of the programmatic supply chain, allowing buyers to identify redundant hops and verify the quality of their traffic sources.

Industry participants, including representatives from Amazon Ads, Raptive, and The Trade Desk, have expressed support for the initiative, noting that transparency is essential for building a sustainable marketplace. The proposed model adds custody-taking entities directly to the schain structure, using a specific designation for those not involved in the commercial flow. IAB Tech Lab has opened a public comment period for the specification, which runs until August 21, 2026. To facilitate a smooth transition, the organization plans to release guidance for SSPs and DSPs to coordinate testing and monitor bid health during the rollout.