Telecoms group Odido, formerly T-Mobile Nederland, has been fined €175,000 by the digital infrastructure inspectorate RDI for wrongly processing traffic data in a joint project with national statistics agency CBS.

The project aimed to develop an algorithm that could provide information on the movements of large groups of people, but Odido’s processes breached legislation designed to protect privacy-sensitive data, the RDI said.

While Odido is allowed to use this data – such as the times of phone calls and the locations of callers – for billing, it should not have processed this (raw) traffic data for the CBS project, the RDI said.

The breach lasted from the beginning of 2018 to the end of 2019 and involved traffic data from between 2.5 million and 4.5 million subscribers. The project between Odido and the CBS ended in early 2020.