Posted by Vegard Johnsen, Product Manager, Google Ads Traffic Quality

For the last few months, we’ve been raising awareness of the ad injection economy, showing how unwanted ad injectors can hurt user experience, jeopardize user security, and generate significant volumes of unwanted ads. We’ve used learnings from our research to prevent and remove unwanted ad injectors from Google services and improve our policies and technologies to make it more difficult to spread this unwanted software.

Today, we’re announcing a new measure to remove injected ads from the advertising ecosystem, including an automated filter in DoubleClick Bid Manager that removes impressions generated by ad injectors before any bid is made.

Unwanted ad injectors: disliked by users, advertisers, and publishers
Unwanted ad injectors are programs that insert new ads, or replace existing ones, in the pages users visit while browsing the web. Unwanted ad injectors aren’t part of a healthy ads ecosystem. They’re part of an environment where bad practices hurt users, advertisers, and publishers alike.

We’ve received almost 300,000 user complaints about them in Chrome since the beginning of 2015—more than any other issue, and it’s no wonder. Ad injectors affect all sites equally. You wouldn’t be happy if you tried to get the morning news and saw this:

Not only are they intrusive, but people are often tricked into installing them in the first place, via deceptive advertising, or software “bundles.” Ad injection can also be a security risk, as the recent “Superfish” incident showed.

Ad injectors are problematic for advertisers and publishers as well. Advertisers often don’t know their ads are being injected, which means they don’t have any idea where their ads are running. Publishers, meanwhile, aren’t being compensated for these ads, and more importantly, they unknowingly may be putting their visitors in harm’s way, via spam or malware in the injected ads.

Removing injected inventory from advertising
Earlier this quarter, we launched an automated filter on DoubleClick Bid Manager to prevent advertisers from buying injected ads across the web. This new system detects ad injection and proactively creates a blacklist that prevents our systems from bidding on injected inventory. Advertisers and agencies using our platforms are already protected. No adjustments are needed. No settings to change.

We currently blacklist 1.4% of the inventory accessed by DoubleClick Bid Manager across exchanges. However, we’ve found this percentage varies widely by provider. Below is a breakdown showing the filtered percentages across some of the largest exchanges:

We’ve always enforced policies against the sale of injected inventory on our ads platforms, including the DoubleClick Ad Exchange. Now advertisers using DoubleClick Bid Manager can avoid injected inventory across the web.

No more injected ads?
We don’t expect the steps we’ve outlined above to solve the problem overnight, but we hope others across the industry take action to cut ad injectors out of advertising. With the tangle of different businesses involved—knowingly, or unknowingly—in the ad injector ecosystem, progress will only be made if we all work together. We strongly encourage all members of the ads ecosystem to review their policies and practices and take actions to tackle this issue.