Ads.txt – Authorised Digital Sellers

While ads.txt revolves around advertising, the ads part is actually an acronym that stands for Authorized Digital Sellers.

Ads.txt is an initiative by the Interactive Advertising Bureau IAB to enable publishers to take control over who can sell their ad inventory. Simply put It is an IAB-approved text file that aims to prevent unauthorized inventory sales to promote and improve transparency in programmatic advertising.

Why ads.txt ?

The issue of domain spoofing / arbitrage selling of inventory has been a major scourge for a long time, even though the latter is not really illegal, packaging and repackaging of the same inventory for a higher price by middle men without adding any value to the traffic don’t help neither the publisher nor the brands, through ads.txt both Brands and publishers benefit from the following…

  • Transparency – The inventory supply chain becomes more open.
  • Control – Publishers will have more control over their supply.
  • Authorized Sellers : brands will be able to identify genuine source of traffic.
  • Confidence : Brands can be more confident as to where their ads are being displayed.

Ads.txt  Publishers.

The publishers can drop an ads.txt file in the root domain of their website with the following information.

  • Ad tech Platform: The Platform that the publisher uses – Appnexus, Pubmatic, Rubicon…
  • Publisher ID: The Publishers identification of the exchange / ad network through which the inventory is sold.
  • Direct Seller / Resller : Depends on whether the publisher authorizes another company to sell their inventory (Reseller) or chooses to work directly with the Ad tech company.

Ads.txt – Advertisers

Earlier in June 2017 the IAB tech labs had released a crawler that can pull ads.txt files from publishers websites which can help brands identify the rightful owners of the websites.

Also advertisers can also see for themselves if a particular seller is indeed legitimate. For example – if you wanted to check if the “Huffington post” inventory that you bought was indeed from a genuine source – you could go to to see if the exchange that you bought the traffic from is listed as an authorized seller.

Adoption of ads.txt till now has been limited to large publishers but is expected to catch up amongst the smaller players as well. This delay in the implementation can attributed to the lack of developer resources that exchanges and publishers  have at their disposal, having to implement ads.txt and to monitor them when the supply chain grows in length.

The menace of ad fraud is expected to exist in one form or the other but implementation of ads.txt is a start to get things cleaned up.