During the Flash Crash on May 6, 2010, a short period of high stock market volatility, some stock prices declined to $0.01, while others increased to $100,000. Examining Intermarket Sweep Orders (ISO) before, on, and after May 6, we find that ISO use is substantially higher on May 6. For those...

We study NYSE, NASDAQ, and ARCA prices for DJIA stocks and LSE, Xetra, and Chi-X prices for five leading British equities. MiFID1 hastened fragmentation but accomplished the intended cointegration of European equity markets that had previously been segmented. Initially, price discovery in London...