Spotify 'to withhold certain premium albums' for paying subscribers only
Spotify is said to be thinking about making certain "premium" albums available to paying subscribers only.
At the moment the music streaming service allows users to listen for free, with adverts, or pay a subscription of £9.99 a month.
According to the Wall Street Journal, the Swedish company has come under pressure from artists and record labels to pay more for the music it streams.
Adele and Taylor Swift have both withdrawn their music from Spotify.
Taylor Swift said the free service devalues artists' work. Last year she tried to get her music exclusively on Spotify's paid service but pulled all her music from the service after failing to reach an agreement.
It is still available on subscription-only services such as Apple Music, Rdio, Rhapsody and Beats.
Adele has withheld her latest album 25 from all streaming services, which has translated into record-breaking CD and download sales.
Spotify says its "freemium" model leads to more people paying for its premium service. That also means artists get paid more per stream, it says.
The company is the global leader in music streaming, with 20 million paying customers and 75 million total active users.
Spotify spokesman Jonathan Prince said: "We are 100% committed to our model because we believe that a free, ad-supported tier combined with a more robust premium tier is the best way to deliver music to fans, create value for artists and songwriters and grow the industry.
"In that context, we explored a wide range of promotional options for the new Coldplay album and ultimately decided, together with management, that Coldplay and its fans would best be served with the full album on both free and premium."
Why Spotify likes free
It's understood that Spotify is willing to test out different ways of releasing music but there's no detail on how that might work.
According to the Wall Street Journal, the company would test and track usage of the "premium" approach if it was introduced for certain artists.
Earlier this year, the company didn't make the 10-minute track The Globalist from Muse's latest album Drones freely available, but the track is now on both Spotify's free and paid tiers.
Spotify's free service allows users to listen to an entire album for free playback on computers, or on mobile devices, as long as you listen to adverts and the tracks are shuffled out of order.
A stream from a paying subscriber is thought to earn artists and labels around 10 times what they'd receive from a non-paying user.
Artists and labels are therefore more interested in limiting streaming plays to paying subscribers.
That option is less attractive for Spotify, which is still trying to use its free service as a hook to get more new users.
Other services, such as internet radio service Pandora, randomise playback making it impossible to listen to a single album at once.