Fight Advertising Fraud in Mobile Apps with IAB Tech’s App-Ads.txt

Programmatic advertising has been a game-changer for many online retailers. The ability to automate the buying and selling of ads saves time and streamlines marketing campaigns. However, this modern convenience soon gave rise to another problem: advertising fraud. In other words, unauthorized resellers found ways to claim and spoof inventories as their own, even when they weren’t authorized to sell it.

Enter Ads.txt, a fraud-fighting program released by IAB Tech Labs in 2017. Two years later, the research and development consortium has released a newer version, called App-Ads.txt, that cuts down on mobile advertising fraud within apps themselves.


As an app publisher, adopting this specification allows your in-app advertising inventory to remain eligible and verifiable to programmatic buyers, allowing you to successfully reach your monetization goals. It reduces fraudulent in-app inventory from marketing campaigns, as well as identifying and blocking instances of unauthorized developer impersonation.


Implementing the app-ads.txt specification primarily relies on the following steps, though details may vary depending on your own infrastructure.

  1. Create a publicly accessible website for your app (example:
  2. Specify the website in the developer website section of the app store at the time of your app submission.
  3. On your website, create and publish an app-ads.txt file that should be accessible at /app-ads.txt location (example: Make sure to carefully proofread all content.
  4. The file should be saved as a text file and the content of the file should be one line for each of your direct sellers and resellers. 

How to authorize Tapjoy as a Digital Seller

  1. Define the ad source domain:  For Tapjoy, this will be
  2. Input the publisher ID: This ID is unique for each publisher partner. You can find this information on the Tapjoy Dashboard on the page for your app under Settings. 
    To locate your unique publisher ID, first navigate to your App on Tapjoy Dashboard and then click on the
    App Settings under Settings in the top navigation bar:

    On this App Settings page, select the API Keys tab and Publisher ID is one of the available values:
  3. Designate the relationship type: For Tapjoy, you can put ‘DIRECT.’ Please list Rubicon Project, our programmatic demand provider, as ‘RESELLER.’
  4. List the ad source ID: This is the ad source’s TAG ID. For Tapjoy, this will be 29e595b1aeb5904d

All four parameters must be separated by a comma and a separate line must be used for each authorized partner. Be sure to proofread your file as errors can be costly.

For example, for Tapjoy, and Rubicon Project as our programmatic demand provider, the two entries in the file are:

This IAB-recommended best practice of specifying resellers of your inventory keeps your reach at its fullest potential and helps prevent domain spoofing against your app.

For more information on all things mobile advertising, reach out to the experts at Tapjoy today! 

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