Their execs routine hop from one to the other, and they regularly cross-license samples and other rights to each other.
The Big Three told Spotify that the price of licensing their catalogs would be high. First of all, Spotify had to give significant ownership stakes to all three labels. This put the labels in an unresolvable conflict of interest: as owners of Spotify, it was in their interests for licensing payments for music to be as low as possible.
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