The music industry has long had a strained relationship with streaming sites like Spotify, mostly over licensing issues and claims that artists aren't being paid enough. Now, the Sweden-based service has been hit with a $1.6 billion lawsuit by a music publisher over unpaid royalties.

The case has been brought to a California federal court by Wixen Music Publishing, which owns and represents compositions by Tom Petty, The Doors, Neil Young, Rage Against the Machine's Zach De La Rocha and Tom Morello, Stevie Nicks, and many more. It says Spotify is using tens of thousands of songs by these artists without a license and compensation. Wixen is seeking at least $1.6 billion in damages, according to the Hollywood Reporter.

"Spotify brazenly disregards United States Copyright law and has committed willful, ongoing copyright infringement," states the complaint. "Wixen notified Spotify that it had neither obtained a direct or compulsory mechanical license for the use of the Works."

Back in May, Spotify came to a proposed $43 million settlement for a class-action lawsuit, of which Wixen was a part, brought by songwriters David Lowery and Melissa Ferrick. It alleged that the company failed to pay adequate royalties for the songs it streams.

Spotify was then hit with two more lawsuits in July, and in September, Wixen objected to the Ferrick settlement, which is still waiting to be approved by a judge, calling it an unfair dollar amount. Instead of waiting on a ruling, Wixen has now launched its own lawsuit.

Spotify responded by questioning whether Wixen really has the authority or authorization to take such action on behalf of its clients, especially those that are deceased.