Hesai Group's stock plummeted 8.02% in pre-market trading on Monday, following Morgan Stanley's downgrade of the company from Overweight to Equal Weight (Hold).

The sharp decline in Hesai Group's share price was likely driven by the influential investment bank's decision to cut its rating on the stock. Morgan Stanley also lowered its price target for Hesai Group from $15 to $5.80, further contributing to the negative sentiment surrounding the company.

Analyst downgrades from major firms like Morgan Stanley often weigh heavily on a stock's performance, as they signal reduced confidence and outlook from influential market participants. While the specific reasons behind Morgan Stanley's downgrade are not explicitly stated, the move appears to have significantly impacted investor sentiment towards Hesai Group.