That should help fund his collection of "rare air-cooled Porsches"
"As part of selling WhatsApp to Facebook, Mr. Koum earned about 24.85 million restricted shares, according to his offer letter filed to the Securities and Exchange Commission at the time. The stock has vested in quarterly increments, with the final period taking place in mid-November of this year.WhatsApp Co-Founder’s ‘Rest and Vest’ Reward From Facebook: $450 Million -- WSJ
In mid-May, Mr. Koum collected 2.5 million shares worth about $458 million at the time, according to a securities filing. In mid-August, he is set to collect another 2.5 million shares, or about $450 million at Facebook’s stock price of $181 at Tuesday’s close.
The stock awards have been contingent on Mr. Koum being employed at Facebook during that time, or “subject to continued service to us through each vesting date,” according to one Facebook securities filing. Mr. Koum fulfilled that requirement by showing up at Facebook headquarters about once a month, according to two people familiar with the matter. It is unclear what he did on his days in the office or how long he stayed."