Spotify is a fascinating and a very young company, founded in 2006, just over 10 years ago. They even have a Dublin office. In Jan 2016 Spotify acquired Dublin music discovery start-up Soundwave. They have 19 regional offices and a number of other development and operations centres.
Spotify is what some would call a high-tech unicorn company - a unicorn is a startup company valued at over $1 billion - many of them, like Twitter and Uber (and Airbnb until recently), have never made a profit.
Spotify has over 1,000 employees (>1,600), 90 million subscribers and close to $2 billion in annual revenues (ref 2015). Think about that, a revenue of about $1.2 million per employee. Shares in the company are privately held but at the most recent fund-raising round (2015) it would have been valued at $8.5 billion. In intervening years it raised a further $1.5 billion through convertible bonds. There is talk of an IPO (initial public offering) on the stock market in 2018. Your guess is as good as mine as to what value it will float at. You will find more statistics at Statista