Germany's highest court has ruled in favour of a hip-hop artist who used a two-second sample of music from the pioneering electro-pop band Kraftwerk.
Kraftwerk's Ralf Hutter sued Moses Pelham, alleging that his use of the clip, without asking, infringed the band's intellectual property rights.
But the German Constitutional Court decided that the impact on Kraftwerk did not outweigh "artistic freedom".
The sample came from the cult band's 1977 song Metal On Metal.
The dispute centres on a short drum sequence looped repeatedly in the song Nur Mir (Only Me) by Sabrina Setlur.
In 2012 Germany's Federal Court of Justice (Bundesgerichtshof) ruled that Setlur's song should no longer be promoted, agreeing with Hutter that it amounted to copyright infringement.
Now the constitutional court in Karlsruhe has sent the case back to the federal court, saying it must reassess the case.
The top court believes that blocking Pelham's sample would "practically exclude the creation of pieces of music in a particular style".
In November Hutter had told the Karlsruhe court that it was incumbent on Pelham, as a fellow musician, to ask permission before creating the sample. Pelham copied the track in 1997.
Before Tuesday's ruling the German Federal Union of the Music Industry warned that an attitude of "artistic freedom trumps everything" could have far-reaching consequences. The union's director Florian Druecke said such a position "would be grist to the mill for those who claim that everything should be allowed on the internet".
German media say Pelham got support from the singer Sarah Connor, rapper Bushido and reggae musician Gentleman.