Yun Li / CNBC : AMTD Digital, a Hong Kong-based fintech popular on WallStreetBets, briefly sees its market cap top $300B and its stock jump 21,400% after its July 2022 IPO — – AMTD Digital, a little-known Hong Kong-based fintech company, saw its shares skyrocket 126% on Tuesday alone after experiencing a series of trading halts.