Art Zelin/Getty ImagesThe “Stairway to Heaven” copyright infringement trial is set to begin in less than four weeks, and lawyers representing the interests of late Spirit guitarist Randy California want to make sure that Robert Plant and Jimmy Page are in the courtroom when the trial starts.

According to The Hollywood Reporter, a lawyer has brought a motion to compel Plant and Page to be in attendance. Francis Malofiy, who represents the trustee that manages Califonia’s estate, says in the filing that Led Zeppelin’s attorneys told him the pair plan to attend the trial, but could not be certain exactly when. Malofiy wants to make sure the pair are present from the start.

California’s estate has sued claiming the opening of “Stairway” improperly takes from Spirit’s 1968 instrumental “Taurus.” The trial is set to begin June 14.

At issue in the case will be a whether or not Page and Plant heard “Taurus” and whether any similarities between the two tunes involve commonly used musical elements not unique to “Taurus,” as well as several procedural questions — such as whether California had previously waived the right to claim copyright infringement.

Also, late last month, U.S. District Judge R. Gary Klausner ruled that a jury will be able to consider only the elements of “Taurus” that are part of the sheet music deposited with the Copyright Office in 1967, and not any recordings of the song.

While the statute of limitations has run out on Led Zeppelin being liable for back royalties, they could still be forced to pay royalties earned by “Stairway to Heaven” in the future if they lose.

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