Led Zeppelin's lengthy copyright battle over "Stairway to Heaven" appears to be over. The U.S. Supreme Court has refused to hear arguments, leaving in place a lower-court ruling that found no infringement.

Jimmy Page and Robert Plant have been involved with various legal actions for six years after the estate of songwriter Randy California charged them with plagiarizing the intro from a 1968 song called "Taurus" by Spirit. This new action follows a March victory in the Ninth Circuit Court of Appeals, which upheld an earlier jury verdict in Led Zeppelin's favor.

The Ninth Circuit ruling was notable in that it overturned an "inverse-ratio rule" that had served as precedent in copyright cases for more than four decades. To win a copyright-infringement case, plaintiffs have to show that someone had access to the their client's work and that the two items were "substantially similar." The inverse-ratio rule focused on access, holding that the more familiar the accused was with the copyrighted work, the less similarity was required.

The Ninth Circuit noted that access has become much more widely distributed in the digital age, leaving a notably lower burden of proof. "It was a terrible rule," Ed McPherson, an attorney who filed an amicus brief supporting Led Zeppelin, told Variety. "If you have a lot of access, that shouldn’t mean there should be a lesser standard to prove copyright infringement. It's never made sense to me."

More than that, the court argued that "we have never extended copyright protection to just a few notes. Instead we have held that 'a four-note sequence common in the music field' is not the copyrightable expression in a song."

Journalist Michael Skidmore filed the initial lawsuit against Led Zeppelin in 2014 on behalf of the estate of the late California, whose real name was Randy Wolfe.

A jury ruled against the estate in 2016, but then a three-judge panel from the Ninth Circuit took the case up again in 2018. They argued that the earlier jury had been given poor instructions and ordered a new trial. Led Zeppelin then appealed to the broader Ninth Circuit bench.


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