Interactive Brokers Chairman Thomas Peterffy explains the rationale behind his brokerage firm's decision to put restrictions on investing in companies like GameStop Corp., citing systemic risk as one of his biggest worries.
Koss Corp., whose stock is among those skyrocketing in recent weeks amid support from the WallStreetBets message board, swings to a profit in its second quarter.
Shares of videogame retailer GameStop Corp. and theater chain AMC Entertainment Holdings Inc. regained some ground after hours Thursday following a drop in the regular session when brokerages set restrictions on trading.