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Publisher: Is your site clean?

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To address the challenges around publisher-seller transparency, the team at video discovery platform Primis has created, a free tool for publishers. The intention? To make it easier for publishers to manage and communicate publisher-seller transparency to their advertiser and agency partners. Primis’ Livnat Mor explains more…

We just returned from Advertising Week in New York, and transparency was a major theme.

Though transparency means different things to different players in the digital advertising ecosystem, publishers have an opportunity to improve advertising revenue through publisher-seller transparency.

To address publisher-seller transparency, the IAB launched ads.txt (the acronym for Authorized Digital Sellers) in May 2017. It’s a text file intended for publishers to host on their web servers that lists the vendors authorized to sell the publishers’ ad offerings.

Ads.txt is a great idea, but implementation has been a challenge for publishers. Currently, 45% of the 1,000 leading domains have implemented ads.txt. But even for those 45%, managing ads.txt is a continuous process. Every time a publisher’s relationship with a vendor changes, ads.txt needs to be updated. This means that whenever a new vendor is added or removed, or even if a direct seller becomes a reseller, the ads.txt file needs to be updated. And this is a challenge for time-starved publisher ad ops teams.

We’ve seen that there are a lot of mistakes in ads.txt files. Many of these mistakes are due to changes in a publisher’s relationships with vendors. But there are other issues that can impact publisher-seller transparency which are an indication that a publisher’s traffic might not be clean – free of fraud and malicious actors.

To address the challenges around publisher-seller transparency, our team at Video Discovery platform Primis created, based on ads.txt and sellers.json data. Due to our vast experience working in the advertising ecosystem, we wanted to create a solution that makes it easier for publishers to manage and communicate publisher-seller transparency to their advertiser and agency partners. We strive to accomplish this through a tool showing publishers potential red flags regarding their sellers according to their ads.txt file, with suggestions for how to fix any issues and improve publisher seller transparency.

Errors and misrepresentations of relationships between a publisher and the publisher’s sellers in ads.txt files comprise a not small percentage of the errors we find in ads.txt. For example, 85% of the 130,000 domains that crawls have at least one misrepresentation. And the red flags we’ve found indicate that a publisher’s ads.txt file isn’t clean, damaging publisher-seller transparency. Red flags include the same seller listed as a direct seller and a reseller, and a publisher listed as a reseller. But a publisher working with too many sellers or with a seller working with a large number of publishers might also trigger a red flag.

Data from gives a publisher an indication of how accurate their ads.txt is while also enabling marketers to have greater confidence in the publishers they’re choosing to work with. You can think of the score like a Good Housekeeping seal for publishers. Based on the number of direct sellers a publisher works with, the accuracy of the relationships listed, and any errors or misrepresentations in the ads.txt files, one can get an indication of how clean a publisher is likely to be. recently conducted a ranking of the leading publishers according to their content category. As you can see in the table below, Food, Home & Garden, Lifestyle, and Travel & Tourism scored higher while News & Media, Games, and Sports scored lower. Furthermore, except for two vertical categories (Vehicles and Travel & Tourism), the larger sites ranked lower in than the smaller ones (those with fewer site visitors).

How clean is it? Publisher site verticals ranked by score

With marketers increasingly focusing on transparency, it’s important for publishers to make sure that their ads.txt files are up-to-date. But perhaps more important, to ensure publisher-seller transparency, marketers need to verify they’re working with clean publishers free of fraudulent and malicious traffic.

One of the best ways to accomplish this is to work with publishers who have clean ads.txt files which will be highlighted by a relatively high score in

Livnat Mor
Director, Strategic Partnerships. by Primis is a free tool shedding light on the ad tech supply chain by comparing ads.txt files with sellers.json files including tools such as the Wizard, an ads.txt editor for publishers. The tool is an initiative for the AdTech industry to help publishers and buyers gain insight into the authenticity of the parties who mediate between them. By doing so, we hope to promote transparency as well as curb ad fraud and other malpractices casting a shadow over the AdTech ecosystem.

The was developed by the team leading Primis, a video discovery platform used by hundreds of digital publishers across the world. Primis is owned by Universal McCann and The Interpublic Group of Companies, Inc. (NYSE: IPG).