Coinbase’s mushrooming cold wallet balance underscores the persisting trend of investors trusting third parties with their Bitcoins
Source: https://cointelegraph.com/news/exchanges-hold-more-bitcoin-than-ever-as-coinbase-wallet-nears-1m-btc
Exchanges Hold More Bitcoin Than Ever as Coinbase Wallet Nears 1M BTC
January 24, 2020
CoinTelegraph