Image: Niko Mannonen / Yle

Swedish-Finnish telecoms operator Telia is selling customers' location data to cities and private entities, the company has confirmed.

Cities can use the data to track the movement of people in specific geographical locations. Telia’s aggregation service shows where people are coming from and in which parts of the city people spend the most time. This information is then be used to help companies decide where to set up shop while providing city officials with information useful for public transport planning.

Telia downloads the location data from cellular relay stations. This means the link station is able to share location data even if users switch off geo-tracking (GPS) settings on their devices.

However, customers would have to give explicit permission for a carrier to sell any identifying data, according to Helsinki University communications law professor Päivi Korpisaari.

"Selling location aggregation services to third parties is in no way a necessary part of carriers’ business," Korpisaari told Yle.

Tapio Levä, a senior business manager at Telia, said because the data is anonymised third parties would not be able to use the location data to map out individuals’ routes between home and work.

"Algorithms collect the data automatically before any person has access to the information. Identifying information is peeled off right away," Levä explained.

Tracking an individual is not possible, according to Levä, which suggests that Telia’s location aggregation service complies with the user terms customers sign onto when activating a Telia mobile subscription.

Last summer, the city of Helsinki tapped into Telia’s location aggregation service to learn from where tens of thousands of people were coming to attend Ed Sheeran’s concerts.

The city of Jyväskylä meanwhile used Telia’s data to map the liveliness of its downtown area as residents increasingly flock to suburbian shopping malls outside the town centre.