This research paper investigates Mini Flash Crashes, also referred to as Flash Equity Failures, in US equity markets by analyzing data from the four most volatile months between 2006 and 2011. The study challenges prior research by identifying regulation framework and market fragmentation as the key drivers of these events, rather than other factors previously considered. Specifically, it highlights the role of aggressive Intermarket Sweep Orders and the limitations of Regulation NMS, which only protects the Top of the Book, in precipitating these crashes.

The methodology involves empirical analysis of market data during high-volatility periods, focusing on regulatory impacts and fragmentation effects. The findings reveal strong evidence that Mini Flash Crashes have a detrimental effect on market liquidity and are associated with Fleeting Liquidity, where liquidity appears and disappears rapidly. This work contributes to quantitative finance by providing new insights into market microstructure and regulatory implications, emphasizing the need for policy adjustments to mitigate such disruptions in high-frequency trading environments.