The business that would be King began life as online games developer Midasplayer in Stockholm in 2002 - even overnight successes take a fair bit of time to mature. Brit VC Apax invested $35m in September 2005 and the first iteration of Candy Crush launched on King.com in March 2009.
But it was the shift to Facebook two years later that was the winning move. Although others - Zynga's Farmville for one - arrived earlier at the social gaming party, Candy Crush, with its short, sweet and mobile-friendly gameplay, has reaped the greater spoils.
An addictive confection in which players match glittering on-screen sweeties by shape or colour, the game has been downloaded 500 million times and has been Facebook's most popular app since January last year.
It is also the highest grossing app on Google Play and earns an estimated $630,000 per day on Apple's US App Store alone.
King made profits of over $700m on revenues of $1.9bn last year. With numbers like that, no wonder the firm has announced its intention to float on the NYSE. Raising $500m at a sugar-coated valuation of up to $7.6bn would make it the most valuable London-based tech IPO ever - if investors can be persuaded to swallow the pill.
Who's the boss?
With an Italian CEO, a Swedish creative head and a chairman from, er, Derby, King is the very epitome of a 21st-century 'borderless business'. They all stand to do pretty well from the IPO. Chief exec and reformed management consultant Riccardo Zacconi owns 10.4% of the equity, but chairman Melvyn Morris is the biggest individual shareholder, with 12.2%.
The founder of dating site uDate and a former director of Derby Country FC, Morris left school at 16 to sell flooring but could end up worth £500m.
The secret formula
King's 180 games are free to download but make money when players buy in-game power-ups to boost scores. Although only 4% of the firm's estimated 344 million monthly users do so, that's enough to generate a ripe old income.
But Candy Crush accounts for 78% of all revenues, so King's big challenge is to do it again. It needs repeat successes to prove it's not just another Zynga-style, one-hit wonder.
Tax planning. Founded in Stockholm with an executive team based in London and a float planned in New York, perhaps it's no surprise to learn that King's official HQ is somewhere else again, in 'tax-friendly' Dublin. So don't expect HMRC to be cheering if and when King gets its float away.
Employees: 600 approx