One of the most frequent warnings we see in Google Ad Manager is the yellow bar across the top of the page  stating Warning – Please review your ads.txt setup to prevent potential revenue impact.  Such high-impact warnings are always a concern and no publishers wants to risk “potential revenue impact”, but the help that the warning links to does not always help to resolve the issue. 

Ads.txt is the initiative to give buyers confidence that the ads they are buying are being displayed on the website that they claim to be. The idea is simple: Each website declares what accounts are authorised to sell on their behalf by listing those accounts in a text file on the site. This file sits in document root and is named ads.txt. We discuss implmenting ads.txt for AdSense and Ad Manager in this post.

What does the warning mean?

When Google Ad Manager believes you are serving Google Ads on a domain that has not authorised the account then it will display the warning “Warning – Please review your ads.txt setup to prevent potential revenue impact”.  Google will look for a line in each ads.txt file authorising each linked account that is serving ads to that domain. If it is unable to find and understand any of those lines then the “Please review your ads.txt setup” warning is shown.

What can the potential revenue impact be?

Google ads (meaning AdSense and Ad Exchange ads) will only be shown on domains with the appropriate ads.txt authority. This means that no revenue will be generated from Google ads for that combination of domain/account until the issue is resolved.

My file looks fine – why the warning?

There are a number of reasons why Google Ad Manager may not find the authority it requires:

• The ads.txt file does not exist : If the file does not exist then no authority can be granted. You can check this by viewing the ads.txt file in your browser, ie www.example.com/ads.txt
• One of more account IDs are missing :  It’s not enough to say “this domain is authorised to sell inventory on AdSense”, a line has to appear for each account that will serve ads
• The file is incorrectly formatted : Ads.txt files have to be formatted in a specific way. If the formatting isn’t correct then it won’t be understood
• Google is unable to crawl the file : Even if the file is present, complete and correctly formatted, Google could be blocked from crawling and processing it. The most common cause of this is that it is blocked by the robots.txt file on the domain.

Help! I’m still getting the warning

Even when all those conditions are met, some publishers continue to see the warning, which can be confusing and frustrating. If you are getting the warning, but clicking the Ads.txt Management link shows that 100% of queries are authorised, then the warning is a false flag.  In this situation it is safe to click the “Dismiss” link.