How WhatsApp's billionaire CEO spent the year after the $19 billion Facebook acquisition

Sequoia CapitalWhatsApp co-founders Jan Koum and Brian Acton.

It’s been exactly one year since Facebook acquired mobile messaging company WhatsApp for $US19 billion.

The groundbreaking deal made both of the app’s cofounders billionaires.

Originally from Kiev, Ukraine, CEO Jan Koum moved with his family to the US when he was 16 years old. The family struggled and lived on welfare and food stamps.

With an estimated net worth of $US6.8 billion, Koum has certainly come a long way since his food stamp days.

In a somewhat symbolic move, Koum signed the paperwork for the Facebook acquisition on the door of his former welfare office. The office is located just a few blocks away from WhatsApp's headquarters in Mountain View.

Suddenly, as of February 2014, Koum was a billionaire.

The WhatsApp team celebrated the Facebook deal by popping bottles of Cristal champagne. Igor Solomennikov, one of WhatsApp's first employees, posted this photo to Instagram, though he later took it down. A bottle of Cristal typically costs about $200.

Source: Business Insider

They also took some time to party during their time in Barcelona. Koum celebrated the acquisition and his 38th birthday with a massive, paparazzi-filled party at a night club called Boujils.

Source: Daily Mail, Tumblr

Mark Zuckerberg and Priscilla Chan were also in attendance. Koum and Chan happen to share a birthday.

Source: Daily Mail

But even though he's now worth billions, Koum has carried his money-saving ways into adulthood. According to a message he posted on Flyertalk, Koum pressured Facebook to close the deal before he missed his flight to Barcelona, which he had purchased using frequent flier miles.

Source: Gizmodo

Though Koum does own a Porsche -- which he bought before the Facebook acquisition -- he dislikes being called an entrepreneur and says he prefers to focus on building a great product rather than on acquiring wealth.

Source: Business Insider

And just months after his company was acquired, Koum made a serious turn to philanthropy, quietly making a $556 million donation to the Silicon Valley Community Foundation.

Source: SFGate

The WhatsApp acquisition was finalised in October, and Koum officially joined Facebook's board. Like many other CEOs in Silicon Valley, he agreed to a yearly base salary of $1, with stock options worth nearly $2 billion.

Source: Wall Street Journal

But in the meantime, Koum has stuck to his hobbies, like poker, boxing, and ultimate frisbee.

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