This piece by Aswath Damodaran is a great explanation of why Facebook paid $19 billion for Whatsapp. There's a lot there, but it's an elegant read.
Returning to the Facebook/Whatsapp deal, it seems to me that Facebook is playing the pricing game, and that recognizing that this is a market that rewards you for having a greater number of more involved users, they have gone after a company (Whatsapp) that delivers on both dimensions. Here is a very simplistic way to see how the deal can play out. Facebook is currently being valued at $170 billion, at about $130/user, given their existing user base of 1.25 billion. If the Whatsapp acquisition increases that user base by 160 million (I know that Whatsapp has 450 million users, but since its revenue options are limited as a standalone app, the value proposition here is in incremental Facebook users), and the market continues to price each user at $130, you will generate an increase in market value of $20.8 billion, higher than the price paid. Are there lots of "ifs" in this deal? Sure, but it does simplify the explanation.
Bonus content: an explanation of the difference between how traders and investors see the world.
This week, I was at the Tuck School of Business at Dartmouth, talking about the difference between price and value. I built the presentation around two points that I have made in my posts before. The first is that there are two different processes at work in markets. There is the pricing process, where the price of an asset (stock, bond or real estate) is set by demand and supply, with all the factors (rational, irrational or just behavioral) that go with this process. The other is the value process where we attempt to attach a value to an asset based upon its fundamentals: cash flows, growth and risk. For shorthand, I will call those who play the pricing game "traders" and those who play the value game "investors", with no moral judgments attached to either. The second is that while there is absolutely nothing wrong or shameful about being either an investor (No, you are not a stodgy, boring, stuck-in-the-mud old fogey!!) or a trader (No, you are not a shallow, short term speculator!!), it can be dangerous to think that you can control or even explain how the other side works. When you are wearing your investor cape, you can be mystified by what traders do and react to, and if you are in your trader mode, you are just as likely to be bamboozled by the thought processes of investors. So, at the risk of ending up with a split personality, let me try looking at Facebook's acquisition of Whatsapp for $19 billion, with $15 billion coming from Facebook stock and $4 billion from cash, using both perspectives.