Spotify may soon allow musicians to reserve their albums for paying subscribers only, according to a report from the Wall Street Journal. Currently, music must be made available to both paying subscribers and those using the free ad-supported service, something which has proved to be a sticking point for artists like Taylor Swift, who pulled her entire catalogue from the service last year.

According to Spotify's artist guidelines, the service pays between $0.006 and $0.0084 per stream to rights holders, but notes that "the effective average per-stream payout generated by our Premium subscribers is considerably higher." If artists are able to focus their efforts purely on Spotify's 20 million paying users, the amount they earn per-stream might be reasonable enough to encourage artists like Taylor Swift to re-join the service.

The report adds that Spotify will be implementing the change with one artist initially in order to investigate how the approach might affect usage and subscription sign-ups. Who that artist might be remains up for discussion, but Spotify is said to have been in talks with Coldplay and the album "Head Full of Dreams." The deal fell through because the group's management couldn’t guarantee that it could keep the album off other free sites such as YouTube, according to the WSJ's sources.

In a statement, Spotify's global head of communications and public policy, Jonathan Prince, confirmed the discussions with Coldplay, but defended its current business model.

"We are 100 percent 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," said Prince.

"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 this Friday."

Earlier this month, UK artist Adele withheld her new album "25" from the Spotify and other streaming services. She sold more than 4.5 million copies on CD in the first two weeks after its release. While not all artists are as popular as Adele, no doubt Spotify doesn't want others following her lead.