Vodafone Germany sued for storing customer's mobile traffic data

In addition, the IMEI is used to identify the subscriber and is associated with the caller ID, said Vodafone. Data about incoming calls will only be saved if they have billing relevance, which is the case when it concerns roaming calls, Vodafone added.

"My client doesn't have a home tariff anymore and therefore does not have a need for location based services," Starostik said in a statement posted to his website. "That is why I filed a complaint with the district court of Dû³¥¬¤orf," he said, adding that lawsuits from other customers against other telecom service providers will follow soon.

Starostik's client is one of "many" that responded to a call from the Working Group on Data Retention issued last September seeking users who want to complain about the storage of their data by telecom providers, he said.

The storing of traffic data is a privacy issue that makes everyone a suspect, Tangens said. "It is pathetic to argue that the data is needed to battle terrorists," she said, adding that the storage of traffic data at a central place could be very convenient for law enforcement agencies or well-connected private detectives to track someone down or figure out who he has been calling and where he has been.

The ability to track a person's whereabouts with mobile traffic data was demonstrated by the German politician Malte Spitz, who collaborated in 2011 with the German newspaper Die Zeit to incorporate six months of telecom data in an interactive map. Whoever hits the play button on the infographic can track Spitz's whereabouts almost by the minute within the time span of half a year.