LOS ANGELES: Led Zeppelin's lawyers asked a judge to throw out a case accusing the band's songwriters of ripping off a riff for 'Stairway to Heaven.' The estate of Randy Wolfe, founder of the band Spirit, failed to prove it owned the copyright to his 1968 song 'Taurus' or that it was substantially similar to 'Stairway,' attorney Peter Anderson said. 'Plaintiff rested and failed to carry his burden of proof on multiple issues,' Anderson wrote in a motion to dismiss Monday. US District Judge R. Gary Klausner is expected hear arguments on the motion when the trial resumes Tuesday morning. Wolfe's estate claims that guitarist Jimmy Page and singer Robert Plant incorporated a unique musical phrase from 'Taurus' in the introduction to their 1971 rock epic. Anderson said attorney Francis Malofiy had failed to show that members of Led Zeppelin were familiar with the song and experts had not presented a convincing case that the tunes were similar enough to amount to copyright infringement. Musical experts for the Wolfe estate said there were many similarities between the obscure instrumental 'Taurus' and 'Stairway,' but a defense expert testified Friday that the main similarity was a common descending chord sequence used as a musical building block for 300 years. Anderson also said the plaintiff failed to show actual damages from any infringement or present evidence of revenues from 'Stairway.' An economist testified that Led Zeppelin works that include 'Stairway' earned nearly $60 million in revenues in the past five years, but that included other works, as well, and didn't include manufacturing costs or other expenses that could be deducted. Anderson asked Klausner to make the judgment before the case goes to the jury. The motion is fairly typical after the plaintiff rests in a case. Messages left for Malofiy were not immediately returned.