App-ads.txt furthers fight against ad fraud

IAB Australia recommends the adoption of app-ads.txt to help fight ad fraud

App-ads.txt is an extension to ads.txt and is suitable for advertising within in-app environments on mobile and OTT (over-the-top), or any other app inventory. The ‘ads.txt’ stands for Authorised Digital Sellers and is a simple, flexible and secure method that publishers and authorised partners can use to publicly declare the companies they have sanctioned to sell their digital inventory.

IAB Australia recommends local publishers to adopt this solution as a method of helping to eliminate the ability of criminal entities profiting from counterfeit inventory in the open Australian digital advertising ecosystem. Digital buyers can in turn now use both app-ads.txt and ads.txt files to help shift media spend to authorised supply paths.

How does app-ads.txt work?

App-ads.txt supports apps distributed through online app stores, linking app store listings to app developer websites. A standard process is provided in the documentation to help publishers obtain the app developer’s website URL from an app listing page in an app store. App developers publishing authorizations in an app-ads.txt file on the developer’s website centralize this configuration into an online resource that the developer independently controls. Using a developer domain creates a universal namespace, which may help identify and block instances of unauthorized developer impersonation.

Outside of providing this app-to-developer domain link, participants should view the handling of the domain-to-authorized seller enforcement as nearly identical to that used in ads.txt for web inventory, aside from the subdomain handling. 

Working example (provided by REA Group), 9607, DIRECT, 0bfd66d529a55807, 139947, DIRECT, 5d62403b186f2ace, 7870, DIRECT, f5ab79cb980f11d1, 184900, DIRECT, 50b1c356f2c5c8fc, pub-1821430187985601, DIRECT, f08c47fec0942fa0, pub-3750446276746305, DIRECT, f08c47fec0942fa0, 4913, DIRECT, 6c33edb13117fd86, 228454, RESELLER, 7842df1d2fe2db34, 228454, RESELLER, 7842df1d2fe2db34, 504, RESELLER, 59c49fa9598a0117

Pubmatic app-ads.txt Adoption dashboard

Designed for mobile buyers to monitor the progress of app-ads.txt adoption, this handy dashboard displays weekly data from both the Google Play and Apple App Stores.

As buyers, accessing fraud free, legitimate inventory on behalf of our brands is crucial, as is supporting our local publisher partners and the Australian online advertising ecosystem. As an industry it is imperative that we work together to combat fraud in any way we can, utilising the technology we have available. The adoption of App-ads.txt will further increase confidence for buyers, sellers and importantly for app developers. The adoption of ads.txt provided an increase in advertiser and publisher confidence, and it is fantastic that we can now extend this to App.

Braden Clarke

Executive Manager, Audience Solutions & Automated Trading, REA Group

Last week marked exactly one month since app-ads.txt was officially released. It's still early in the ecosystem and adoption is taking its own time - there's a long way ahead. Even though app-ads.txt's benefits are undeniable, there is a lot of education that needs to be put in place across the ecosystem. Realistically speaking, DSPs cannot really drive adoption until critical mass is reached. It's the duty of SSPs and exchanges to promote and push for it. The demand side will be able to help by mandating app-ads.txt, but only after a sufficient share of the developers have implemented it.

Sergio Serra

Product Management, Supply & Programmatic, InMobi

At Telaria we believe a transparent, fraud-free ecosystem is vital for programmatic trading. App-ad.txt for in-app and OTT/CTV is that next step following on from the success we’ve seen with ads.txt, Open measurement and ads.cert. As OTT and CTV usage grow, it’s important to ensure that buyers and sellers transact with confidence in a trusted environment, and this is the right solution to legitimise in-app inventory across mobile and CTV devices. This moves our industry in the direction of increased clarity and transparency and we support it wholeheartedly.

James Young

General Manager, Telaria

As an early adopter of the ads.txt standard for web inventory, we’re pleased to adopt the recently released app-ads.txt standard for in-app inventory.


We support the IAB’s Authorised Digital Sellers initiatives as a means to increase trust and transparency across the digital supply chain – ensuring buyers can effectively navigate the path to authorised supply of genuine inventory.


 As witnessed with the adoption of the ads.txt standard for web – critical mass on the supply side is a required before this data can provide full value to DSPs and programmatic buyers. We would encourage other premium publishers and app developers to implement this simple solution to help overcome domain spoofing; and direct DSPs and buyers to authorised supply paths.

Georgina Fox

Publisher Partnerships and Supply Director, GroupM

© 2019,IAB Australia