Image copyright Capitol Records Image caption Katy Perry had been ordered to pay $550,000 of the total $2.8m damages in the original trial

Katy Perry's smash hit Dark Horse was not copied from a Christian rap song, a US judge has ruled.

The ruling overturns a jury's verdict from last summer, which said Perry's song lifted an eight-note riff from Flame's 2009 song Joyful Noise.

In her decision, US district judge Christina A Snyder said the sequence of notes was "not a particularly unique or rare combination".

As a result, Perry's team no longer owe Flame $2.8m (£2.3m) in damages.

Snyder drew on the testimony of the rapper's own witness, musicologist Todd Decker, in concluding the jury had reached the wrong verdict.

"A relatively common eight-note combination of unprotected elements that happens to be played in a timbre common to a particular genre of music cannot be so original as to warrant copyright protection," she wrote.

Perry's lawyer Christine Lepera had made a similar argument during the trial, saying that Flame was "trying to own the basic building blocks of music".

She welcomed Judge Snyder's ruling, calling it "an important victory for music creators and the music industry".

Led Zeppelin's influence

The decision to overturn the jury's finding comes a week after a similar case involving Led Zeppelin's Stairway to Heaven was overturned by the US Circuit Court of Appeals for the Ninth Circuit.

That case also involved questions about whether simple musical motifs could be copyrighted; and the verdict, which was in Led Zeppelin's favour, was quoted in Judge Snyder's ruling on Dark Horse.

The Led Zeppelin ruling may also affect a high-profile copyright claim, over Ed Sheeran's Thinking Out Loud.

That case - in which Sheeran is alleged to have copied elements of Marvin Gaye's Let's Get It On - had been due to go to trial last September, but the judge paused it pending the outcome of the Stairway to Heaven appeal.

Despite Tuesday's ruling, however, the Dark Horse case may not be over just yet. Judge Snyder said that if an appeals court disagreed with her ruling, she would conditionally grant a new trial.

Flame's legal team have already indicated they intend to appeal.

"When the jurors returned a unanimous verdict of infringement, I cautioned my clients that we had only finished Round 11 of a 15-round match and that the next round would take place in the court of appeals," said the rapper's lawyer, Michael A Kahn.

"We believe the jury was right and will do our best to restore their verdict on appeal," Kahn said.

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