Geolocated advertising data can be used to track EU officials, even to their homes

SOLÈNE REVENEY / LE MONDE

Every second, millions of pieces of personal data are exchanged on the online advertising market. The information, sourced from apps installed on smartphones, is sometimes linked to precise geolocation data. The companies that have the data can therefore track millions of mobile users, sometimes down to within just a few meters.

The advertising market, in which mobile users' personal data is traded and sold, most of the time thrives without users being aware of it. It benefits from loopholes in personal data laws, particularly the General Data Protection Regulation (GDPR), which the European Union adopted in 2016, after much debate.

A new investigation into personal data brokers, conducted by the Belgian daily newspaper L'Echo, the German specialist news website Netzpolitik.org, the Dutch and German radio stations BNR and BR, together with Le Monde, shows that no one is spared by this out-of-control industry – not even those who are supposed to design and implement European data protection law.

Several EU officials identified