Marty O'Donnell and Mike Salvatori, the composers who made the original Halo soundtrack including its driving combat music and iconic "monk chant," are suing Microsoft for unpaid royalties going back 20 years.

As reported by Eurogamer, O'Donnell and Salvatori filed suit in Washington State District Court back in June 2020. Depositions and discovery have been completed and mediation is set to begin next week. If mediation fails to resolve the dispute, both parties will head to trial.

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At issue are what O'Donnel and Salvatori say are unpaid royalties for the use of Halo's music. The lawsuit lists six complaints related to breach of contract and Microsoft failing to provide an accounting of all due royalties. Microsoft's counterclaim seeks a declaration by the court that the Halo music qualifies as work-for-hire and therefore wouldn't require royalty payments.

"It was never work-for-hire," O'Donnell told Eurogamer in an interview. "It was always a license deal. So that's what we did with Halo. With the first Halo music ever, that was written and recorded in 1999 for the first time. It was licensed to Bungie. Bungie didn't get bought by Microsoft for over a year."

Bungie hired O'Donnell in 2000 to work as the studio's audio director. Salvatori remained independent, but both still worked as part of O'Donnell Salvatori Inc., which retained the rights to the Halo music and licensed it to Bungie for use in its games. Ten days after being hired by Bungie, the Halo developer was purchased by Microsoft, which then needed to take over the licensing agreement.

O'Donnell and Salvatori have received royalties over the years, but according to the pair, Microsoft has never provided them with an accurate accounting of those royalty payments. Both became suspicious after years of soundtrack sales that didn't seem to line up with the 20% royalty figure they were expecting.

As for the TV show, O'Donnell has instructed their lawyers to explore a possible injunction against the show's premiere on Paramount+ due to these unpaid royalties. Neither O'Donnell nor Salvatori has been credited in the show, although the Halo monk chant has been used in prior promotional material.

This is hardly the first time O'Donnell has gotten litigious with his works. O'Donnell sued Bungie for unpaid wages after being wrongfully terminated in 2014. Later, Bungie sued O'Donnell for using unreleased Destiny music in his album "Music of the Spheres," which the court ordered destroyed and O'Donnell to pay $100,000 in damages.

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