U.S. attorney Francis Malofiy, who represents late Spirit guitarist Randy California, filed court papers in Pennsylvania last year (14), alleging the British rockers stole the band's opening riff from 1968 song Taurus for Zeppelin's 1971 classic after serving as Spirit's opening act in the late 1960s.

Malofiy is hoping to prevent the future release of the remastered Led Zeppelin IV album, which features the track, until his late client receives proper credit for the song.

Led Zeppelin were denied their request to have the suit dismissed on jurisdiction grounds last year (14), and earlier this month (May15), a judge ruled the case will now be heard in Los Angeles.

Surviving Led Zeppelin stars Jimmy Page, Robert Plant and John Paul Jones have since filed a response to the lawsuit, dismissing the allegations.

In the paperwork, they acknowledge playing a concert with Spirit, "but otherwise deny each and every allegation" in the lawsuit.

More: Led Zeppelin are being sued for plagiarism | Contactmusic.com

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