The Robinhood and Interactive Brokers platforms have restricted trading in GameStop stock and options on Thursday morning, triggering a significant backlash among retail investors who decried the move as market manipulation. It follows steps taken by TD Ameritrade and Charles Schwab on Wednesday. “We continuously monitor the markets and make changes where necessary. In light of recent volatility, we are restricting transactions for certain securities to position closing only, including $AMC, $BB, $BBBY, $EXPR, $GME, $KOSS, $NAKD and $NOK. We also raised margin requirements for certain securities,” Robinhood said in a statement explaining the move. Interactive Brokers explained why it is suspending trading of the stock and others like AMC Theaters, Koss, Express, and BlackBerry: “As of midday yesterday (1/27/2021), Interactive Brokers has put AMC, BB, EXPR, GME, and KOSS option trading into liquidation only due to the extraordinary volatility in the markets.” “In addition, long stock positions will require …