That means that Sony still gets $30m from Spotify, but only $10m is "attributable" to a specific recording artist who can make a claim on it. The rest of the money is Sony's to play with: they can spread it around all their artists, some of their artists, or none of their artists. They can spend it on "artist development" (which might mean sending top execs on luxury junkets to big music festivals). It's theirs.
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