Not much would happen if recent history is a guide. One day in mid-September 2017, $4.2 billion of Bitcoin changed hands, and the price that day went up about 5%. That volume followed a rumor that China was cracking down on cryptocurrency exchanges.

I can't say I spend much time watching the tape, but I have seen >100-BTC trades on GDAX in the past, and at current prices your what-if scenario involves a sale of about 909 BTC.

https://www.cryptocoinsnews.com/11-billion-24-hour-cryptocur...