Evan Spiegel is cashing in, and it's a big payday. The CEO of Snap Inc. was given more than 37 million shares of Snap stock as a bonus for taking the company public, according to a document filed with the Securities and Exchange Commission.

The 26-year-old billionaire reached an agreement with Snap's investors in 2015 that would award him 3 percent of the company's outstanding shares as a bonus for the IPO. It was intended to motivate Spiegel to grow the business, according to Snap's IPO filing:

Our board of directors approved the award to Mr. Spiegel in July 2015 to motivate him to continue growing our business and improving our financial results so that we could undertake an initial public offering, which we regard as an important milestone that will provide liquidity to our stockholders and employees.

And motivate it him it did: At Snap's current stock price of $21.44 per share, that bonus is worth almost $800 million.

On March 2, Snap began trading on the New York Stock Exchange for $24 a share. The company's public offering was expected to the biggest U.S. technology IPO in five years, and even had traders running practice trials on the weekend before trading began.