Three weeks after Apple Music's launch, Apple CEO Tim Cook said "millions and millions of customers" had already signed up for the new streaming service, which certainly sounded impressive (though vague). We weren't expecting to hear any hard numbers so soon after Apple Music's release, but music industry insiders are saying more than 10 million people have subscribed in less than a month.

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The numbers come from music industry trade publication Hits Daily Double. Record label execs are bound by Apple's non-disclosure agreements to keep quiet, but multiple sources told the pub that Cupertino is sharing the 10 million subscriber stat with song rights-holders to prove Apple Music is already a competitive service. Some songs have racked up as many streams on Apple Music as on Spotify.

Apple Music is currently offering a free three-month trial, so those subscriptions don't translate into revenue. Current users might not stick around once their free trial is up (and some have cancelled already). But of Spotify's 75 million active users, only 20 million pay $9.99 for a premium membership. Spotify is currently offering new users a three-month premium subscription for 99 cents, and it's unclear how many of those enrolled in the trial are counted in Spotify's premium subscriber stat.

Why this matters: Apple has an advantage over Spotify in that Apple Music comes preinstalled with iOS 8.4, which saw a quick rate of adoption in the days after its release. Combined with the free trial, it's surprising that Apple doesn't have even more subscribers--though with many users reporting trouble combining their iTunes libraries with Apple Music's streaming catalog, perhaps some potential customers are hanging back to see if Apple can improve its new service before signing up.

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