Coinbase (NASDAQ:COIN), the largest crypto exchange in the US, saw a massive movement of Bitcoin out of its coffers this week. On Monday, numbers released by the company showed an outflow of about 18,000 BTC worth $924,253,200 million as of today, Feb 21st. This movement leaves the exchange with 390,000 bitcoins, or about $20 billion. This is the lowest amount of bitcoin reserves Coinbase has held since 2015. There is little reason to be alarmed, however. This is most likely funds being moved to set up new custodial wallets or provide funding for OTC transactions. Some see this as a potentiall…