The world's largest internet exchange point is suing the German government for tapping its communications systems.

DE-CIX runs a number of critical exchange points – most of them in Germany, but with others in France, Spain and the United States – and has sued the German interior ministry over orders from the German security services to allow them to tap its exchange centers.

The goal of the lawsuit, filed in federal court in Leipzig, is to reach a "judicial clarification" over whether the German government's actions are legal, the company said (in German), and "in particular, legal certainty for our customers and our company."

According to DE-CIX, its customers – typically large ISPs from around the world – have pressured the exchange point to seek clarity over the legality of tapping its centers.

A recent paper by a German constitutional lawyer claimed that the actions of the German intelligence services (BND) were "completely illegal," arguing that the degree of surveillance was "disproportionate" and failed to account for whether the communications covered German citizens or not.

Like in many countries, the German government is – theoretically at least – not allowed to spy on its own citizens. The issue of state surveillance is also a very serious topic in the country due to its dark history, particularly the actions of the Stasi in East Germany from 1950 to 1990.

DE-CIX references the paper [PDF, in German] by Prof Dr Hans-Jürgen Papier, past President of the Constitutional Court, stating that it casts "weighty doubts about the legality of the current practice."

The paper specifically tackles the issue of the BND tapping internet exchange points and frequently cites DE-CIX. It notes that the company's Frankfurt internet exchange point is "one of the world's largest Internet exchange points with currently more than four terabits throughput at peak times."

Generous

Under the current regime, the BND is given a raw data stream from the exchange point and officially is only supposed to search it for specific phone numbers and email addresses. But under what Papier notes is a "rather generous interpretation" of the law, the BND does far more, equating to mass surveillance.

DE-CIX also references the G10 Act, which is Germany's equivalent of the US Foreign Intelligence Surveillance Act (FISA). Like FISA, the German system comes complete with a secretive court, and has faced claims that it is unconstitutional, sparking demands for reform.

The G10 Act is named after Article 10 of the German constitution, which covers privacy of correspondence, posts and telecommunications. The act was scrapped in part following Edward Snowden's revelations of mass surveillance in which Germany, the US, and UK worked together to spy on each other's citizens and share the information.

Since then there has been significant pressure brought to bear on the BND to reform: reform that the organization resisted, leading to the resignation of its director earlier this year. The decision by the German Federal Constitutional Court that much of the BND's surveillance was unconstitutional has also shaken things up.

But the German establishment and security services are still attempting to resist serious efforts at reform. The DE-CIX lawsuit may prove to be a critical stepping stone in that effort. ®