A scam artist netted millions without breaking any laws thanks to an incredible scam on Spotify, an exposé has revealed.

The unknown operator, based in Bulgaria, uploaded music clips for which they legally owned the copyright to the streaming service.

They then set up thousands of accounts to continuously play back these tracks, likely using software bots to automate the process, to hack Spotify's pay-out system.

By raking in the royalties generated each time the songs were played they were able to earn a vast amount of money over four months, industry sources have said.

Altogether, over the four months, a pair of playlists may have generated revenues of more than £2.2 million ($3million).

The ploy was only discovered when the scam proved so successful that the high volume of traffic for the lists came to the attention of major record labels.

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By raking in the royalties generated each time songs were played, they were able to earn a vast amount of money over four months. The ploy was only discovered when the scam proved so successful that the high volume of traffic for the songs came to the attention of record labels

In an in-depth report for Music Business Worldwide (MBW), journalist Tim Ingham first revealed the bogus activity.

It was uncovered after two suspicious playlists, called Soulful Music and Music From The Heart, were noticed at the top of Spotify's global playlist charts.

Each week, the music streaming service sends confidential figures to industry insiders that rank playlists by the amount of money they have earned.

In late September 2017, both spurious lists had climbed higher than any other playlist created by a major label, sparking interest from the industry.

They spotted a number of suspicious red-flags, which rang alarm bells over the playlists' authenticity.

This included the short duration of the tracks and the obscure artists behind them, as well as the low number of subscribers yet high numbers of listens.

A scam artist netted millions without breaking any laws thanks to an incredible sleight of hand trick on Spotify, an exposé has revealed. It was uncovered after two suspicious playlists called Soulful Music (pictured) and Music From The Heart were noticed in Spotify's global charts

Digging further they found evidence of a money-making scheme with a potential payout of up to $415,000 (£300,000) each month for the top ranked playlist alone.

Quoting an anonymous source, MBW said: 'Spotify was sharing this weekly detailed data with the major labels, Merlin and other rights-holders for months before it was flagged up.

'All the while, it looks pretty plain that somebody was using purchased library music to extract hundreds of thousands, perhaps millions, of dollars, out of a royalty pool that would have otherwise gone to them and their artists.

'You can’t completely blame Spotify for this, because every one of these accounts was presumably attached to verifiable income.'

Only plays by Spotify Premium paid for accounts are included in the total number of plays and the music clips themselves are thought have been bought and paid for.

All this means the scam, while underhand, probably doesn't break any laws.

It does beg the question, however, how many other users of the service are making money by manipulating Spotify's pay-out system.

The unknown operator uploaded music clips which they legally owned the copyright to. They then set up thousands of accounts to continuously play back these tracks, likely using software bots to automate the process, to hack Spotify's pay-out system

In a statement, a spokesman for Spotify said: 'We take the artificial manipulation of streaming activity on our service extremely seriously.

'Spotify has multiple detection measures in place monitoring consumption on the service to detect, investigate and deal with such activity.

'We are continuing to invest heavily in refining those processes and improving methods of detection and removal, and reducing the impact of this unacceptable activity on legitimate creators, rights holders and our users.'