An IAB Tech Lab standard that lets app publishers declare which ad networks are authorized to sell their inventory.

Where do I put the app-ads.txt file?

At the root of the developer website listed in your App Store / Google Play page, e.g. https://studio.com/app-ads.txt.

What is a Certification Authority ID?

An optional TAG-ID of the ad system, the 4th field of an app-ads.txt record.

liberation.fr achieves the best ad optimization: its app-ads.txt has no errors and matches what its 4 ad networks expect (100% of 8 lines).

Checked 20 Oct 2026. 55 lines, 49 unique records, 0 duplicates, 0 invalid lines, 8 ad networks detected.

Index Exchange — accounts 185598, 191700, 185597: 3 lines in the file
TripleLift — accounts 10318, 10318-EB: 2 lines in the file
Google AdMob — accounts pub-1005272636684943, pub-4445562815347109, pub-8528564786755741: 3 lines in the file
Magnite (Rubicon) — accounts 17912, 17914: 2 lines in the file
Mintegral — partner (reseller) lines only: 12 lines in the file, 400 expected lines missing
Yango Ads — partner (reseller) lines only: 20 lines in the file, 400 expected lines missing
DSP Exchange — partner (reseller) lines only: 14 lines in the file, 400 expected lines missing
Bidmachine — partner (reseller) lines only: 13 lines in the file, 400 expected lines missing

Yes — https://liberation.fr/app-ads.txt has 55 lines (checked 20 Oct 2026).

Its app-ads.txt lists Index Exchange, TripleLift, Google AdMob, Magnite (Rubicon), Mintegral, Yango Ads, DSP Exchange, Bidmachine.

liberation.fr achieves the best ad optimization: its app-ads.txt has no errors and matches what its 4 ad networks expect (100% of 8 lines).