GameStop shares hit $160 at the open before being halted after several minutes of trading and fell to around $129 before the second halt. The stock resumed trading around 10 a.m. Eastern and hovered around $143 in late morning trade, up 56%.

The rally lifted other "stonks" popular on sites such as Reddit's WallStreetBets, with AMC Entertainment Holdings Inc up 12.5% and headphone company Koss Corp up nearly 61%.