Ads.txt is a simple, flexible, and secure method for publishers and distributors to declare who is authorized to sell their inventory, improving transparency for programmatic buyers. Ads.txt supports transparent programmatic digital media transactions and can remove the financial incentive from selling counterfeit and misrepresented media. Similar to robots.txt or sitemap.xml, ads.txt can only be posted to a domain by a publisher’s webmaster, making it valid and authentic. Because publishers sell their inventory through a variety of sales channels, ads.txt supports the following types of supplier relationships:
Domain owners who sell on exchanges through their own accounts
Networks and sales houses who programmatically sell on behalf of domain owners
Content syndication partnerships where multiple authorized sellers represent the same inventory
Where to host the Ads.txt file:
Your Ads.txt file should be placed on the root level of your domain. For example, if your domain is widespace.com, you should place the ads.txt file here: widespace.com/ads.txt.
The file must be on the root level of the domain
The file must be a .txt file extension
The file must have Read permissions set to World
The file must follow the IAB format
The instructions are encoded as a formatted plain text object.
The format logically consists of a non-empty set or records, separated by line breaks.
Widespace Ads.txt Details
widespace.com, [Publisher Account ID], DIRECT improvedigital.com, 1166, RESELLER pubmatic.com, 156098, RESELLER, 5d62403b186f2ace
*All records should be included within the ads.txt file.
Ads.txt Fields Explained:
Field #1 (Required) – Domain name of the advertising system.
Field #2 (Required) – Seller Account ID; For publisher account users, please contact your account manager for this ID if you do not already know your account ID.
Field #3 (Required) – Type of Account/Relationship
Field #4 (Optional) – Certification Authority ID
More details on ads.txt can be assessed on IAB’s ads.txt page via below link: