How Spotify's college-dropout founder became a self-made millionaire at 23 — and a billionaire at 35

Thirty-five-year-old Spotify co-founder and CEO Daniel Ek is the tech industry's newest billionaire after the popular music streaming service went public on Tuesday in a massive direct listing, which valued the company at over $26 billion at the close of its first day of trading. Ek's roughly 9 percent stake is worth nearly $2.5 billion.

But Ek is no stranger to making large sums of money at an early age. In fact, the Swedish-born founder became a self-made millionaire at only 23 years old, two years before he'd even launched the first Spotify application.