ads.txt – Authorized Digital Sellers

IAB Tech Lab’s ads.txt Specification version 1.0.1 is currently implemented in the digital ad industry to fight against fraud and misrepresented domains. Click the button below to view the spec.


IAB Tech Lab released “Mobile App Support for ads.txt,” guidance for business and operations teams that focus on in-app advertising. ads.txt, a simple, flexible and secure method that publishers and distributors can use to publicly declare the companies they authorize to sell their digital inventory. In public comment for 30 days, this proposal will facilitate ads.txt ad fraud protection within mobile app marketing.

The guidance is available for public comment through July 6, 2018. Finalized guidance can only be delivered after the open areas detailed in the “Mobile app support for ads.txt” document are resolved. There is not yet a set timeline for delivery of a finalized specification. Questions and comments can be sent to openmedia@iabtechlab.com.


IAB Tech Lab offers “ads.txt aggregator” – a critical tool to support its ads.txt anti-fraud initiative. This service provides daily updates on publishers’ approved ad sellers, making it easier for marketers, agencies, and platforms to eliminate fraudulent inventory sources, and fight against domain misrepresentation.

As part of a broader effort to eliminate the ability to profit from counterfeit inventory in the open digital advertising ecosystem, ads.txt provides a mechanism to enable content owners to declare who is authorized to sell their inventory.

Previous Version: ads.txt Spec Version 1.0 | Blogpost

What is the ads.txt project?

The mission of the ads.txt project is simple: Increase transparency in the programmatic advertising ecosystem. ads.txt stands for Authorized Digital Sellers and is a simple, flexible and secure method that publishers and distributors can use to publicly declare the companies they authorize to sell their digital inventory.

By creating a public record of Authorized Digital Sellers, ads.txt will create greater transparency in the inventory supply chain, and give publishers control over their inventory in the market, making it harder for bad actors to profit from selling counterfeit inventory across the ecosystem. As publishers adopt ads.txt, buyers will be able to more easily identify the Authorized Digital Sellers for a participating publisher, allowing brands to have confidence they are buying authentic publisher inventory.

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The IAB Tech Lab OpenRTB Working Group has developed the ads.txt spec. Questions can be sent to OpenRTB@iabtechlab.com

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