Webull Plummets 9.09% as Regulatory Scrutiny Drives 175th U.S. Market Volume Rank

On October 10, 2025, Webull (BULL) closed with a 9.09% decline, trading on $750 million in volume, placing it 175th in U.S. market activity. The selloff followed reports highlighting regulatory scrutiny over its commission-free trading model and user data privacy practices. Analysts noted the drop reflected investor caution amid broader sector volatility, though no direct operational disruptions were disclosed by the firm.

Recent filings revealed a strategic shift toward expanding its institutional client base, a move that analysts say could dilute retail investor influence in the short term. The company also announced plans to integrate AI-driven portfolio analytics, a feature expected to compete with offerings from major brokerage platforms. However, questions remain about execution timelines and potential margin pressures from zero-commission models.

Back-testing results for a hypothetical strategy selecting the top 500 U.S. stocks by daily trading volume showed limitations in current evaluation tools. The existing system supports single-security analysis or event-based testing but cannot dynamically manage large, rotating portfolios. To proceed, users must either simplify to fixed ETF proxies like SPY or await expanded data interfaces capable of handling daily rebalancing across hundreds of equities.