ads.txt
ads.txt/app-ads.txt are text files hosted on a website that allow advertisers and buyers to see who is authorized to buy and sell ad inventory.
The files contain a list of Authorized Digital Sellers (ADS) who resell the inventory of the website or app.
These files are an Interactive Advertising Bureau (IAB) initiative to prevent unauthorized ad sales.
Website ads file
Advertisers send web crawlers to websites from which they are receiving ad requests.
These check the ads.txt file to verify if the crawler’s sender is on the list. If not, they will typically decline to bid on ad requests from that website.
Most buyers and advertisers re-crawl the ads.txt file at least once every 24 hours.
Installation
During onboarding, you will receive a merged version of your current ads.txt file, that contains
the new Publift lines, with any existing lines placed under the #Legacy header at
the bottom of the file.
This file should be uploaded to the root of your website.
https://mywebsite.com/ads.txt
App ads file
In the case of apps, advertisers send web crawlers to the app-developer home page.
These check the app-ads.txt file to verify if the crawler’s sender is on the list. If not, they will typically decline to bid on ad requests from that app.
Most buyers and advertisers re-crawl the app-ads.txt file at least once every 24 hours.
Installation
During onboarding, you will receive a merged version of your current ads.txt file, that contains
the new Publift lines, with any existing lines placed under the #Legacy header at
the bottom of the file.
These files must be uploaded to the root of the website you have nominated as the developer site, for example:
https://mydevelopersite.com/app-ads.txt
Troubleshooting
It will take up to 24 hours before changes to ads.txt are recognised by bidders. Please be patient.
If you are still having difficultly, Google provide a useful troubleshooting resource.
Updating
Publift will monitor your ads files on a monthly basis, and will notify you if changes are required. For example, because a new header-bidding partner has been added.
If so, you can merge your existing file with the Publift latest, being sure to retain any existing lines
in the #Legacy section.