• by Gavin O'Malley  @mp_gavin, October 10, 2018

The European Union’s General Data Protection Regulation -- or GDPR -- did not impact all ad trackers equally, new research suggests.

Taking the hardest hit, smaller ad trackers lost somewhere between 18% and 31% of their reach, according to analysis from Cliqz and Ghostery.

By contrast, Facebook suffered a decline of just under 7%, while Google was actually able to increase its reach by just over 1%, the data privacy specialists found.

For their findings, Cliqz and Ghostery analyzed the top 2,000 domains in Europe in the months before and after GDPR went into effect, this past May.

What explains the uneven impact of the GDPR?

Among other possible explanations, Google, Facebook, and other tech giants were able to dedicate significant resources complying with the regulation, Cliqz and Ghostery suggests.

In addition, Google might have used its dominant market position to encourage publishers to reduce the number of tech vendors, and thus, the number of trackers on their sites.

“Google benefits indirectly from the effects of the GDPR, which led the online advertising market in Europe to become more concentrated, as the majority of advertisers lose market share,” the new report suggests.

As not to risk penalties, it’s also possible that Web site owners preferred to play it safe and drop smaller advertisers, which may have had a harder time proving compliance.

From April to July of this year, the average number of trackers per page on European sites dropped by almost 4%, Cliqz and Ghostery found.

The opposite was true in the United States, where the average number of trackers per page increased by 8%.

In the wake of GDPR’s rollout, most trackers per page are still located on news websites, according to Cliqz and Ghostery. On average, they embed 12.4 trackers.