I heard somewhere that they keep some of each digital currency on hand to help with price stabilization between when you buy and when transfer is done. So like

I heard somewhere that they keep some of each digital currency on hand to help with price stabilization between when you buy and when transfer is done. So like, you buy not from someone selling, but from Coinbase's stash, who then buys to refill from someone else. No idea how accurate that is though, maybe someone can back me up or correct me here