James Dennin, Kapitall: Candy Crush maker King filed for an IPO. The company is already profitable, but will that be enough? King Digital Entertainment is the maker of Candy Crush - the online mobile game which has turned into one of the internet's fattest cash cows. And this morning the company announced that they're going public. Read more from Kapitall: The Olympics: Big Business from Start to Finish? King's leaders have been planning this for a while, filing confidentially last year as profits surged over 7000%. King Digital is much, much more profitable than many of stocks that went public in 2013, particularly in tech, where the focus is usually on product or growth. King makes almost $2 billion in revenue, and have a net profit margin around $500 million. That dwarfs even some tech giants like Amazon (AMZN), whose profit margin was less than 1% last year. And yet the IPO is still inviting skepticism, even more so than hot IPOs like Twitter (TWTR), because King makes pretty much all of its money off three games. And as the tale of Zynga (ZNGA) may suggest, one company producing two hit games is a little like hoping that lightening will strike the same place twice. Which raises the question: is profitability enough to court investors? Does it even matter that much? We decided to look back at 2013's class of IPOs, ranking them based on the highest pops on their IPO day. An IPO pop is the amount the share price rises on the first day, between the actual offering and the market's close. Typically, organizers shoot for an IPO pop of around 15%. That's because there's a very tricky balance to be struck: you don't want too much of the money raised to go to investors, as the company needs it grow. That's why it's going public.