Robinhood says due to “recent volatility” it is restricting trading in certain stocks, including GameStop, AMC, BlackBerry, and Nokia (Maggie Fitzgerald/CNBC)

Maggie Fitzgerald / CNBC:
Robinhood says due to “recent volatility” it is restricting trading in certain stocks, including GameStop, AMC, BlackBerry, and Nokia  —  Amid the flurry of speculative activity in GameStop, brokers took steps to restrict the trading in GameStop stock and options and other related securities.