Robinhood Markets (NASDAQ:HOOD) stock rises as much as 14% in Monday trading, and as much as 46% from its all-time low of $9.94 hit on Friday after Cathie Wood's ARK Investment bought almost 2.45M shares in online brokerage. ARK Innovation ETF (ARKK +8.3%) purchased 1.95M shares of Robinhood (HOOD) on Friday. The ARK Next Generation Internet ETF (NYSEARCA:ARKW) added 230,519 shares, and the ARK Fintech Innovation ETF (NYSEARCA:ARKF) acquired 262,938 shares on the same day. Also see from Friday: Robinhood bounces up after dropping to all-time low. Robinhood's (HOOD) stock price is still more than 60% below its IPO price of $38, when it launched in July.