Taylor Swift and Spotify may have broken up last year, but the two still have bad blood.
The 25-year-old Swift earned a reputation as an advocate for artists, songwriters and producers when she removed her music catalog from the streaming service in late 2014.
Most recently the singer-songwriter took on tech giant Apple for not paying professionals during a three-month free trial for its new music streaming service. The company quickly course-corrected and has since agreed to compensate artists.
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Swift opened up in Vanity Fair's September issue about Spotify and Apple's surprising response.
"Apple treated me like I was a voice of a creative community that they actually cared about," Swift told Vanity Fair. "And I found it really ironic that the multi-billion-dollar company reacted to criticism with humility, and the start-up with no cash flow reacted to criticism like a corporate machine."
Swift, who has traditionally balked at streaming services, agreed to put her "1989" album on Apple Music because of the company's reaction to her open letter.