Ark Invest, led by Cathie Wood, has increased its holdings in four cryptocurrency-related stocks, including Coinbase and Circle, with a total investment of approximately $16.9 million. On Monday, Ark Invest purchased 45,164 shares of Coinbase valued at $6.85 million, 81,757 shares of Circle worth $6.21 million, 149,422 shares of Bullish for $3.54 million, and 2,943 shares of Robinhood totaling $300,000. All four stocks closed higher on the day of the purchase.