Stock Market Movers: Biggest Losers and Gainers on 21 October 2026

5. DXCM: DexCom (DXCM) extends losing streak to 4th straight day, shedding 6.39% ahead of next week’s Q3 earnings.

4. HSAI: Hesai Group (HSAI) drops 5.72% ahead of Q3 earnings.

3. T: AT&T Inc. (T) loses 6.45% on price target cut from JPMorgan over competition concerns.