The German Federal Supreme Court recently handed down a ruling confirming that Internet Service Providers (ISPs) are allowed to retain the dynamic IP addresses of their customers for a period of seven  days, under the German Telecommunications Act. The court considered that the collection and use of this data was suitable, necessary and appropriate for countering any threats to the functionality of the ISP’s telecommunications operations. It considered that, in light of the cur- rent state of technology, there were no other options available to ISPs for identifying, isolating and, if necessary, remedying any disruptions  to the telecommunications system. The court said that the ECJ’s recent invalidation of the Data Retention Directive did not affect this position.

Judgment of the German Federal Supreme Court (Bundesgerichtshof), July 2014 (German language)