Agency Echelon
Reference

An IAB Tech Lab standard requiring SSPs and exchanges to publish a file identifying every seller they represent, so buyers can trace the path from a bid request back to the publisher and see whether each intermediary is a publisher, an intermediary, or both. Combined with ads.txt and the SupplyChain object in OpenRTB, it gives buyers the data for Supply Path Optimization.

Cite this entry: Agency Echelon. "sellers.json." Agency Echelon Reference, reviewed September 2026. https://agencyechelon.com/reference/glossary/sellers-json/

Reference

A reference library for digital advertising, written and reviewed by the Agency Echelon team. Free to read. No advertising, no sponsorship, no affiliate links, no email gate.

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Reviewed September 23, 2026. Reference text is licensed CC BY 4.0. Privacy