The IAB Technology Laboratory has released app-ads.txt, a mobile extension of its fraud prevention tool, for beta testing and commentary.

App-ads.txt applies the original ads.txt functionality to mobile and OTT video apps. The tool works in a similar fashion, in that an app developer adds the app-ads.txt file to their website, creating a centralized online resource that lists companies authorized to sell on their behalf. This allows marketers to verify that the app developer is a trusted seller. In addition, marketers will be able to purchase advertising with the confidence that they are not being scammed by impersonators.

IAB says that the app-ads.txt beta can be implemented now and then app stores can adopt a standardized way of making the information available. Minimal changes are expected, the company added. The tool will be available for public beta testing and comments through February 4.

It is estimated that marketers lose around $7.2 billion per year to ad fraud, piracy and malware. Ads.txt was created by the Interactive Advertising Bureau Tech Lab’s combat inventory sales fraud. Earlier this year, The Trustworthy Accountability Group (TAG) added a requirement that all publishers implement the ads.txt standard if they want to become TAG Certified Against Ad Fraud.

The new mobile version would extend the tool to the mobile economy, which would help solve multiple problems, according to Google.

“Expanding ads.txt to mobile app inventory is a great move forward for the industry,” said Per Bjorke, senior product manager of Google Ad Traffic Quality in a statement. “It promises to increase transparency in the apps ecosystem, adds a new layer of protection for advertisers, and helps ad dollars flow to the right developers.”

Some IAB members are already implementing the tool and planning internal policies around it. Ad seller Centro, for example, will begin enforcing the app-ads.txt specification in the first quarter of 2019. Centro’s director of RTB platform operations said their platform will bid only on supply paths authorized by participating publishers, calling app-ads.txt an “essential step in eliminating the scourge of fraud from the advertising industry.”

Rakuten Marketing called the app-ads.txt “another step in the right direction to reduce counterfeit app inventory and the reach of bad actors.”

The new tool will also support other supply chain safety initiatives, such as ads.cert. Beta testing is open to anyone interested and access can be requested by emailing