ISPs should not be required to filter internet traffic and block sites to prevent intellectual property infringement, is the conclusion (PDF) of Cruz Villalón Advocate General of the European Court of Justice in the Belgian case between Scarlet and Sabam. Such a measure would violate the right to privacy of communications, the right to protection of personal data and the right to freedom of information as acknowledged by the Charter of Fundamental Rights of the European Union. 

Although the case only concerns Belgian ISP Scarlet Cruz Villalón sees the order as a new obligation of a general nature, intended to eventually be permanently applicable to all ISPs. 

According to Cruz Villalón the Charter of Fundamental Rights accepts that rights and freedoms may be restricted, amongst others on condition that such a restriction is ‘in accordance with the law’. The Advocate General considers that a restriction such as that at issue would be permissible only if it were adopted on a national legal basis which was accessible, clear and predictable. It could not be held, Cruz Villalón found, that the obligation for ISPs to install the filtering and blocking system at issue, entirely at their own expense, was laid down expressly, and in clear, precise and predictable terms in the Belgian law. Also, the obligation imposed on ISP's is both special and ‘new’ and even 'unexpected'.

Cruz Villalón also points out that both the filter and blocking system contain insufficient safeguards. 

The Advocate General concludes to propose the Court to declare that European Union law precludes a national court from making an order, on the basis of Belgian statutory provisions, to require an ISP to implement such a filtering and blocking measure on all internet traffic for the protection of intellectual property rights.