Authorized Digital Sellers in short Ads is an Interactive Advertising Bureau (IAB) which helps to improve the transparency between the publisher and the advertiser who can sell or put the ads on the website. It is used to prevent fraud which is a trend nowadays. You can see the advertiser on your Ads code. There are 4 entities in the ads.txt file. From left to right the Google.com, pub-0000000000000, Direct, f08xxxxxxxxxx 1. The first one is the company which is putting the ads on your website. 2. The second one is your publisher ID which is associated with your advertising company. 3. The third field is the relationship type between you and the advertising company. Whether it is direct or indirect. 4. The last entry is of the ID of your advertising company.