A performance and it's composition are under two different copyrights. Think of it as a book and it's audiobook. The copyright holders think that what Graeth w

A performance and it's composition are under two different copyrights. Think of it as a book and it's audiobook. The copyright holders think that what Graeth was doing was like taking a audiobook, listening to it and transcribing the whole book and then profiting from it. It's not copying the performance, sure, but it is taking a roundabout way to copy another copyrighted work.