This issue concerns a case between five audiobook publishers and the Swedish ISP ePhone which appealed a lower court ruling ordering the firm to hand over information about the users connected to certain IP-addresses.
"It is heartening that the Supreme Court has taken this decision and that the Ipred law will now come under the scrutiny of the EU Court of Justice," said ePhone's lawyer, Peter Helle, to the Dagens Nyheter daily on Thursday.
The Swedish Supreme Court (Högsta Domstolen - HD) in June requested the parties involved to submit their view on whether it is necessary to send the matter for a preliminary ruling to the European Court - decision which was interpreted by experts as a victory for ePhone and taken to mean that the case would head for Luxembourg, a process that can take years.
It was thus no real surprise when on Thursday the Supreme Court made it formal ruling.
Bo Wigstrand, president of ePhone, argued at the time of the preliminary ruling that the law provides for private surveillance in an area that should be the reserve of the police and he does not expect to be forced to hand over his customer's IP information to the publishers.
"One should not claim success in advance but this shows that you can not have laws in which private investigators undertake these types of investigations. The police should do it," he said in June.
When the new Swedish law came into force on April 1st, the five publishers of audio books were the first copyright holders to file a case under the new measure.
The publishers, which include 15 authors who suspected their work has been spread illegally over the internet, demanded to know who owned a server suspected of containing some 2,000 audio book titles.
But ePhone refused to reveal who was using the IP-address in question, pointing out that a password was required in order to gain access to the works stored on the computer.
As a result, the company argued, the sound files weren't publicly accessible and thus the matter wasn't a case of copyright infringement.
The publishers then sought a court order which would force ePhone to divulge information about the users tied to the IP-address.
The Solna district court first ruled in June 2009 in favour of the publishers but the the Court of Appeal (Hovrätten) upheld ePhone's appeal of the decision, ruling that the publishers were unable to prove whether the audio books on the server really had been available to the public.