In a verdict handed down today the Court of Justice of the European Union confirmed that EU Internet service providers can be required to block access to sites engaged in copyright infringement. The decision follows the advice of the Advocate General in a case involving the now-defunct streaming site Kino.to.

Although the dream of blocking sites in the United States was completely crushed along with the now-dead SOPA legislation, music and movie companies across Europe have enjoyed a much smoother ride.

Torrent sites such as The Pirate Bay and KickassTorrents are blocked in several countries around the EU and in the UK, for example, dozens of ‘pirate’ domains are now blocked at the ISP level.

A notable case originating from Austria, however, has been on hold pending a decision from the Court of Justice of the European Union. The dispute saw movie companies Constantin Film Verleih and Wega Filmproduktionsgesellschaft complain that local ISP UPC Telekabel Wien had been providing subscriber access to illegal streaming site Kino.to, a site now shuttered following police action.

The movie companies previously obtained interim injunctions to have UPC block the site, despite UPC arguing that it couldn’t be held responsible for a site that it had absolutely nothing to do with. UPC also noted that there was no court ruling indicating its customers had broken the law.

To settle the matter the Austrian Supreme Court asked the Court of Justice to clarify whether a company that provides Internet access to those using an illegal website could be required to block that site. Today the Court of Justice handed down its long-awaited decision.

The Court found that a person who makes copyrighted material available to the public without permission from rightsholders is using the services of the Internet service provider of the people accessing that content. EU law does not require a specific relationship between the person infringing copyright and the intermediary against whom any injunction has been issued, the Court found.

Addressing UPC’s concerns that none of its customers had been deemed by a court to have acted unlawfully, the EU Court said that proof was not necessary as the law is in place not only to bring an end to infringement, but also to prevent it.

The EU Court added that since any ISP targeted by an injunction is free to carry out its obligations in a way that fits its circumstances, blocking orders do not therefore restrict an ISP’s freedom to conduct its business.

Any injunction must, however, must be proportional so as not to unnecessarily stop subscribers from lawfully accessing information. Furthermore, any blocking measures must have the effect of preventing access to copyrighted content or at least make it more difficult. National courts are required to ensure that these conditions are met.

The take-home from today’s ruling, which follows last year’s advice from the Advocate General, is clear: ISPs can be required to block access to infringing sites but any injunction must be balanced and proportional.