The prince of rap and late singer Prince’s estate are at odds over the Purple One's music.

Prince’s estate is suing Jay Z’s Roc Nation, which owns the rapper’s popular streaming service, Tidal, for copyright infringement. NPG Records Inc. and NPG Music Publishing, previously owned by Prince, filed the lawsuit Tuesday, according to the Minneapolis Star Tribune.

The Star Tribune reported that, prior to the lawsuit, the ongoing dispute was being fought in Carver County District Court. Now, NPG Records and NPG Music Publishing are stepping up the legal action over the claim that Tidal misused its exclusive streaming rights to Prince’s music.

Prior to late pop star Prince's death in April 2016, NPG Records entered into an agreement with Tidal via a signed letter of intent from Aug. 1, 2015, according to the legal documents posted by Pitchfork News. The letter granted an exclusive 90-day license allowing the streaming service to promote Prince’s then-newly recorded LP “HITnRUN: Phase One.” There were allegedly no prior agreements made between the parties for Tidal to stream the music.

The battle between the parties began on June 7, 2016, according to the complaint. That's when “Roc Nation, through its Tidal service, began exploiting some of these works after Prince’s death,” according to the document.

However, this past October, Roc Nation fired back. The company filed a court letter stating there were “various oral and written agreements between relevant parties” enabling Title to stream all of Prince's music. Roc Nation did not turn over these agreements to the court, according to the lawsuit.

In addition, Tidal made a move to secure exclusive rights to Prince’s unreleased music catalog for a sum of $40 million, TMZ reported. Prince's estate claimed that the offer was never made, according to Billboard. Earlier this month, Universal Publishing Group revealed it had received worldwide publishing rights for Prince’s entire music catalog, the Billboard article also noted.

Prior to Prince's "HITnRUN" release, both Prince and Jay Z appeared to share similar values when it came to Tidal's mission to support "the commitment of artist owners that believe in creating a more sustainable model for the music industry."

In July 2015 — before he died — Prince began to pull his music catalog from streaming services with the exception of Tidal. On Sept. 7, 2015, the megastar announced that his new "HITnRUN" album would be available exclusively through Tidal.

“After one meeting, it was obvious that Jay Z and the team he assembled at Tidal recognize and applaud the effort that real musicians put in2 their craft 2 achieve the very best they can at this pivotal time in the music industry,” Billboard reported Prince said in a statement at time.