But that staggering sum wasn't the only thing about the acquisition that's shocking.
After Mark Zuckerberg made him an offer on Feb. 9, WhatsApp CEO Jan Koum apparently crashed the Valentine's Day dinner of the recently married Facebook co-founder and his wife, Priscilla Chan, at their home to finalize the purchase.
That's not all.
"The two men entered into negotiations, eating a plate of chocolate covered strawberries intended for Ms. Chan, the people briefed on the matter said," The Times reports. Business Insider's Nicholas Carlson confirmed the strawberry swipe in his account, too.
Not only did Koum get the money, he also got their strawberries. What likely started out as a romantic night for Zuckerberg and his wife ended up with Zuckerberg agreeing to hand over $19 billion.
We'll bet that Koum had the best Valentine's Day of them all.