We don't know what will happen but there will be a chaos, for sure. As far as I know, it's estimated that he owns up to 1.1 million BTC. There are 19 million bitcoins in circulation. Satoshi owns more than 5% of bitcoins that are in circulation. As far as I know, no private or public company owns as much as Satoshi owns, no other individual and organization owns that much too. Now, imagine, tomorrow comes satoshi with one million bitcoins, what will happen? Panic, absolutely every bitcoin holder will be in panic, every business owner and employees will be in panic because it's the situation that no one has thought about and no one has a plan to deal with it. It's a shock.