While Thanksgiving is an American holiday, internet service providers and users in Europe had reason to give thanks yesterday. The highest court in the European Union overturned a ruling that would have forced a Belgian ISP to preemptively filter Internet traffic to prevent the unauthorized sharing of music files.

The European Court of Justice overturned a ruling by a Belgian court in a suit brought by the Belgian Society of Authors, Composers and Publishers (SABAM). SABAM filed it against Scarlet Extended over alleged illegal peer-to-peer filesharing by Scarlet's customers. That 2007 ruling required Scarlet to filter traffic on its network, so that it could identify and block illegal peer to peer filesharing traffic. It was based on an interpretation of Belgian copyright laws that put the burden of enforcement on ISPs.

Scarlet had appealed, focusing on European data privacy laws, saying that the ruling would in effect force the company to monitor all Internet traffic passing through its network—which would, aside from being technically unfeasible, violate the privacy of its customers. The case has been closely watched by Internet companies in Europe, which were concerned that they could be faced with similar requirements.

In its ruling, The Court of Justice upheld the right of copyright holders to file injunctions against intermediaries over illegal file sharing. But it struck down the provisions of the Belgian court ruling that required filtering, finding that the filtering provisions violated European Union e-commerce laws, and infringed on the rights of Scarlet and its customers. The broad monitoring required to filter file-sharing would "infringe the fundamental rights of [Scarlet's] customers, namely their right to protection of their personal data and their right to receive or impart information, which are rights safeguarded by the Charter of Fundamental Rights of the EU," the court panel wrote.