A study says 30.5% of most popular websites use anti-adblockers

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A study says 30.5% of most popular websites use anti-adblockers

A recent study by University of California, Riverside, and University of Iowa reveals that 30.5% of Alexa top 10K websites use anti-adblock scripts to detect adblock users. You might be surprised by such a great number. The thing is that not all the websites “show” they are using anti-adblock scripts. While some of them might block content with adblock or paywalls, others are using anti-adblockers silently – they detect adblockers and either switch ads or report statistics to their back-end servers.

The researchers state that their results show that anti-adblockers are much more pervasive than previously reported. Their anti-adblock detection results are approximately 5-52 times more than in prior studies. The researchers manually inspected 1000 websites. They found that 66 websites have visible reactions (warnings) and 934 don’t, which indeed represents a huge disparity.

The research found news and media websites are much more likely to use anti-adblockers, as advertising is a key source of income for such publications. The investigation also showed that most websites choose to outsource anti-adblocking to dedicated third-party anti-adblocking service providers.

The research team also revealed some techniques used to maximize the chances of detecting adblocker. One of the approaches is called a “bait”. Baits are elements, images, or scripts which are being monitored and stored. All the information is used to understand how the ads are filtered.

Some scripts use the “pixel” technique, which loads a small piece of an image and then drops a browser cookie for future inter-domain ad re-targeting. This ad re-targeting technique allows publishers to ensure that their ads are served only to people who have previously visited their site. The pixel often contains ads-related keywords in its URL path, and therefore can be used as a bait object to detect adblockers. Most of these scripts also silently report adblocking.

The researchers anticipate a further escalation of the technological battle between adblockers and anti-adblockers.

The full report is available here.

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