The Swedish branch of the IFPI (International Federation of the Phonographic Industry) is hoping a court will order an ISP to hand over the IP address of a web user that has been illegally file-sharing.
IFPI has been battling file-sharing all over the world for a number of years.
In April, a law based on the European Union's Intellectual Property Rights Enforcement Directive (IPRED) went in to effect in Sweden.
The law makes it possible for copyright holders to get a court order requesting ISPs to provide IP addresses linked to computers and users that have downloaded their content, and has opened the door for more aggressive tactics by the entertainment industry.
The lawsuit, which was filed with the Stockholm district court this week, marks the first time the recording industry is trying to take advantage of the law.
The IFPI is planning to file more suits against Swedish file sharers, but will first want to see how this case pans out, according to IFPI lawyer Magnus Mårtensson.
The organisation has handed over proof to the court that the user has made 50 songs available, but the total number of songs is in the tens of thousands, Mårtensson said.
Whether the IFPI gets the identity of the user behind the IP address remains to be seen. Both the publishing industry and movie companies have with mixed results tried to get ISPs to match users to IP addresses.
The publishing industry wanted to get information on the owners of an FTP server used to distribute audio books.
It won the first round, but then lost an appeal against the ruling in October. The case is now going to the country's supreme court.
The movie industry set its sight on file-sharing site SweTorrents, and recently won in the Stockholm District Court.
However, TeliaSonera, the ISP that is supposed to hand over the information, will appeal.
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