Ark Invest has bought $12.5 million U.S. of Bullish (NYSE: $BLSH) stock over the last four days, adding the shares across its exchange-traded funds (ETFs). The investment firm led by Cathie Wood has loaded up on the stock of Bullish, a crypto exchange that caters to institutional clients, as the share price has fallen 7% in recent days. BLSH stock has declined 17% in the past two weeks as the price of Bitcoin (CRYPTO: $BTC) and other cryptocurrencies have struggled. More From Cryptoprowl: Bitcoin has fallen ...