Back at the beginning of 2015, before it launched to the public, e-commerce site Jet used a contest to encourage people to refer others to the site. The winner was a Pennsylvania man who spent $18,000 on online ads, recruiting new Jet users through sites like Facebook and Swagbucks. He received 100,000 shares in the company, which he couldn’t cash in until the company went public or were sold. Today, the company announced that Walmart acquired it for $3.3 billion.

One estimate when the site first launched estimated that he might earn $20 million from the deal, but a few things have happened since then: the company received more investment, which would dilute the value of his shares. Yet the company also was estimated to be worth maybe $1.5 billion not long ago, and Walmart purchased it for more than double that.

The contest’s goal was to sign up new users, and he succeeded, recruiting 8,000 people for the beta version of the site. Entrants in second through tenth place received 10,000 shares each, and they’re most likely now at least millionaires too.

How much each Jet share will be worth hasn’t been disclosed to the public yet, but the contest winner is still really happy that his “investment” has paid off so soon.

“The way I think to describe it is ‘occasional hysterical laughing,'” he told Bloomberg during his lunch break from his day job, because of course he’s still working at his day job.

The Accidental Millionaire in Jet.com’s Sale to Wal-Mart [Bloomberg]

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