The greatest rock band in recorded history is back in the news. And who, hearing their music blast through the dormitory corridors of UC-Berkeley in the fall of 1969, could have predicted that a half-century later, Led Zeppelin would be at the center of a raging copyright law controversy on its way to the United States Supreme Court? Will Jimmy Page have to wear a tie?

Fresh from its sacrilege at being turned into elevator music, the band's "Stairway to Heaven"—perhaps the closest heavy metal could ever get to a love ballad—is the subject of court rulings and a petition for certiorari filed August 11 over claims that it plagiarized the opening bars and intro from a 1967 song called "Taurus" by the band Spirit.

A Los Angeles jury cleared Zeppelin of this infringement charge in 2016. A Ninth Circuit panel reversed the verdict, but it was reinstated by an en banc panel whose decision has sent shock waves roiling through the musical copyright world.

Notably, the Court of Appeal ruled that music copyright—and, therefore, analysis of infringement allegations—is limited to the deposit copy of the music on file at the Copyright Office. (All copyright registration applications must include a "deposit" at the Copyright Office of the work, or a representation of it, being copyrighted.) In the case of music copyrights, this tends to be "bare-bones," often simple sheet music which is a far cry from the final version(s) actually produced and recorded. Put another way, the Courts will not compare the accused music against derivative versions of the copyright.

Lawyers for the estate of Spirit's front man, which brought the suit, claimed in their cert petition to the Supreme Court that this ruling would have dire consequences for the music industry and effectively divest writers and composers (or their publishers) of copyright protection of the fruits of their labors. No doubt this is overstated, but also no doubt if this ruling stands it will represent a major change in music copyright law.

It is rare, of course, that cert petitions are accepted, which requires the votes of 4 of the 9 justices; of the 7,000 to 8,000 petitions filed each term, only about 80 are granted. Given their age, however, maybe some of the Supremes are Zeppelin fans. All we know is that right now there doesn't seem to be a whole lotta love in the music world.

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