According to the source, Rumble (NASDAQ: RUM) shares jumped after Tether disclosed it bought another 1,000,000 RUM shares last week, triggering a headline-driven move in the stock. Source: Tether company disclosure; Nasdaq price data. Tether is the issuer of the USDT stablecoin widely used for crypto market liquidity, connecting this equity disclosure to crypto market infrastructure and trading flows. Source: Tether corporate website.