The European Court of Justice ruled in favor of
This doesn’t really makes file sharing legal, this ensures that Internet Service Providers don’t disclose your name if you use file exchange programs (peer-to-peer or P2P) and someone wants to sue you, because copyright infringement is a civil issue.
The Internet Service Providers are required to give your information if you committed a crime.
This means that in EU you can safely use any P2P program, and if an ISP will give your information to another person that uses this in a civil issue like copyright infringement, you can sue them both the ISP and that person.
This isn’t surprising because EU want that IP addresses to be regarded as personal information.