Eminem’s music publisher, Eight Mile Style, has filed a lawsuit against Spotify, alleging copyright infringement. The suit claims the steaming platform didn’t get proper licenses for the rapper’s music and wants Spotify to compensate the publisher for billions of streams.

There are two prongs to the suit, which was first reported today by The Hollywood Reporter. Spotify is accused of willfully ignoring Eight Mile Style’s ownership of Eminem’s catalogue when deciding how to pay out streaming revenue for his playback metrics. Spotify also allegedly violated sections of the Music Modernization Act (MMA), which passed last October and is designed to help streamline the process by which artists, songwriters, producers, and rights holders get paid for online music streams.

According to the complaint, one of the central disputes is over how Spotify treated massive hits like Eminem’s “Lose Yourself.” Eight Mile Style claims the streaming service labelled the song and others as “Copyright Control,” or a song with unknown rights holders. The complaint similarly alleges that Spotify did not go through the proper process to obtain a license for “Lose Yourself” and other songs, or determine who did own the licenses. “Lose Yourself” was famously written for a film starring Eminem — a film of the same name as the publisher itself! — that won an Oscar in the Best Original Song Category.

Eminem’s publisher claims Spotify knowingly streamed the rapper’s music without a license

Instead, Spotify kept Eminem’s music on the platform, where the artist has amassed more than 32 million monthly listeners. Some of his songs have been streamed hundreds of millions times. Eight Mile Style is accusing Spotify of hosting Eminem’s music, but not paying out the proper royalties, despite knowing full well who owns it. “Spotify has not accounted to Eight Mile or paid Eight Mile for these streams but instead remitted random payments of some sort, which only purport to account for a fraction of those streams,” the complaint reads. Spotify did not respond to a request for comment.

According to Eminem’s publicist, Dennis Dennehy, the artist is not a party to the lawsuit, as Eight Mile Style is owned by the same duo, Mark and Jeff Bass, that produced much of Eminem’s early work under the name F.B.T. Productions. The duo have production credits and some co-writing credits on a number of hit singles, including “Lose Yourself.” As a result, Eight Mile Style owns the rights to a majority of Eminem’s early catalog, Dennehy e. Dennehy tells The Verge that Eminem and his team were “just as surprised as anyone else by this news.”

Richard Busch is representing Eight Mile Style in the lawsuit; THR reports Busch is a legal heavyweight who’s behind multiple precedent-setting cases in music publishing and copyright. That includes Marvin Gaye’s family’s successful lawsuit against “Blurred Lines” songwriters Robin Thicke, Pharrell Williams, and T.I.

Busch also represented Eight Mile Style in a landmark 2010 lawsuit against Universal Music Group imprint Aftermath Records, which negotiated with the Bass Brothers for the licenses to Eminem’s early work. That suit resulted in artist and label-friendly changes to how digital downloads were perceived by the law, by labeling them as a license of copyright and not a physical sale. That in turn increased the royalties paid out for by Aftermath and other labels during a time when iTunes dominated the music industry.

Eight Mile Style seeks damages that could, at the extreme end, amount to billions of dollars. Spotify, which went public last year, is now valued at $26 billion. Eight Mile Style is also seeking statutory damages on a per song basis, with a total of 243 works in question. That could result in Spotify paying tens of millions, although if Eight Mile Style is successful in disqualifying Spotify from protection under the MMA, it could face more severe financial penalties.

Update August 21st, 8:18PM ET: Included details regarding Eminem’s relationship to Eight Mile Style, and the fact that he is not a party to the lawsuit.