The Fish Market suit could expand those definitions even further. In the U.S., most copyright cases focus on melodies, hooks, or lyrics to determine infringement, reflecting the ways that the law relies on what is musically notatable in a classical Western tradition. The Copyright Act of 1909 required songwriters to submit sheet music—known as “deposit copies”—to register copyright. The 1973 revision to that law allowed them to register copyright with a recording, but in the last decade, deposit copies have assumed renewed relevance, as ideas of what can be musically copyrighted are legally contested.

However, the Steely and Clevie case is not based on melody, but on rhythm. The role of rhythm in music copyright has been tested far less in the courts, in part because it’s less commonly notated using sheet music. “If someone wants to express a really complex rhythm, they’re probably not going to sit down and say, ‘Let me get out a blank sheet.’ They’re going to clap their hands,” explains Dr. Olufunmilayo Arewa, a law professor at the Antonin Scalia Law School of George Mason University. Arewa notes that Afro-diasporic music “can’t be notated very well using the conventions that were established during the classical music era, where it was mostly notating melodies and chords, but not really much notation about rhythm.” That means U.S. copyright law has struggled to grasp the creativity embedded in rhythmic musical traditions.

Many legal scholars see this as a Eurocentric bias rooted in the law—and one that has prevented Black artists from making successful infringement claims around rhythm. “The reality is that African-based musics have a very distinctive timbre, and they tend to be rhythmically complex in ways that I think aren’t often appreciated by courts,” says Arewa. In a 2018 article for the Harvard Law Review, scholar Joseph Fishman echoed that sentiment, writing, “A melodic emphasis in music copyright reflects European aesthetic norms that don’t represent much of modern music making, especially within genres pioneered by Black artists. Defining the musical work in terms of melody has discounted and discriminated against wide swaths of these artists’ creativity.”

That’s why the legal implications of the Steely and Clevie case are so huge: A ruling in favor of Steely and Clevie could make it much easier to copyright rhythms overall. It could make the music industry adjust common practices around royalty splits, insurance costs, and even the composition of songs. For example, four years after the “Blurred Lines” case, The New York Times ran a story diving into the case’s effect on songwriters. The story revealed that they were facing “heightened scrutiny of their work while it is still in progress, as record companies and music publishers sometimes vet new songs for echoes of past works.” And as more names started to be added to a song’s credits, royalties were being split across a higher number of composers, which ended up diminishing individual earnings.

How the “Fish Market” instrumental—and its gazillion reworks—became a pillar of reggaeton

First, a basic chronology: In 1989, producers Steely and Clevie wrote and recorded the song “Fish Market,” an instrumental B-side of Gregory Peck’s “Poco Man Jam.” The following year, producer Bobby “Digital” Dixon used elements of that instrumental for Shabba Ranks’ “Dem Bow,” a now-iconic anti-imperialist (and homophobic) dancehall anthem that exploded in the global dancehall and reggae scene. As the court filing explains, the instrumental of “Dem Bow” is an alternative mix of “Fish Market,” based on the same underlying backing track (importantly, Steely and Clevie co-own the copyrights to “Dem Bow.”)