There's no word yet on when the IPO would happen, but Robinhood has filed the confidential plan to go public later this year.
Banking Committee weighs a financial transaction tax and questions payment for order flow during hearing.
Robinhood needed that new investment "because of the antiquated nature of how we settle stock trades," one finance professor says.
After shares of the video game retailer closed down 44% Thursday, they were up about 80% at market open Friday.
Massachusetts regulators say the brokerage app Robinhood makes it too easy for inexperienced traders to buy risky options.