Speculative guess:
Massive @CoinbasePro outflows = OTC deals

It looks like massive Coinbase outflows usually go to their new cold wallet for custody/OTC that held 6000-8000 $BTC.

#Greyscale uses #GenesisTrading for buying Bitcoins, and #GenesisTrading uses Coinbase Custody. https://t.co/iFobwtf1gK