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- GameStop soared as much as 20% on Thursday as more short-sellers closed positions and ran for the exit.
- The company's Monday announcement that it would add activist members to its board kicked off a rally that's left shareholders cheering and squeezed shorts out of their bearish bets.
- The scale to which short-sellers were targeting GameStop likely exacerbated the squeeze. Short interest in GameStop shares reached 135% on January 5, according to S3 Partners data.
- The leap comes after the video-game retailer scored a 57.4% gain on Wednesday that pushed shares to their highest level since August 2016.
- Watch GameStop trade live here.