Bengaluru, April 12 -- On a late February afternoon, singer Ankur Tewari excitedly opened Spotify for Artists, a dashboard that allows musicians to view their content on the streaming app, to check how a new song had been received. Chand Takiye, the single, was still fresh and the latest of the soft, reflective tracks that had earned Tewari a fanbase.

Instead, Tewari was stunned to find a set of songs he had never written, recorded or approved sitting under his name on Spotify, and also on Apple Music.

Tewari is not an artiste easy to mistake for someone else. Over the years, his songs, such as Dil Beparvah and Gehraiyaan, have found a distinct consumer base in the indie pop and acoustic genres. Now, these dozen or so random tracks, com...