GameStop stock (GME) rose 47% on Thursday after a YouTube account believed to be tied to investor Keith Gill, also known as "Roaring Kitty" on social media, posted a livestream scheduled for Friday at noon ET. After the market close, Reddit user DeepF***ingValue, an account previously tied to Gill, posted a new screenshot purporting to show their position in the video game retailer ballooning to $586 million, including stock holdings and unexercised options positions. Earlier this week, the same user revealed they'd paid $175 million for a position in GameStop at that time valued closer to $210 million. Shares ... (full story)