This paper reviews recent theoretical and empirical research on high-frequency trading (HFT). Economic theory identifies several ways that HFT could affect liquidity. The main positive is that HFT can intermediate trades at lower cost. However, HFT speed could disadvantage other investors, and...

This paper revisits the relative pricing of Palm and 3Com shares in 2000. We offer a simple rational explanation of the Palm/3Com price relationship before Palm's spinoff is completed. Lending fees and spin-off uncertainty are crucially important to understanding the relative levels and...

The total effect of a regulatory change consists of direct effects and indirect effects (spillovers), but the standard difference-in-difference approach measures only direct effects and ignores potential indirect effects. By examining the short-sale aggressiveness during the 2007 full repeal of...

We study a set of trading restrictions imposed by Robinhood and other retail-oriented broker-dealers in 38 stocks, including GameStop. Restrictions limit equity and/or options positions. Stock price effects are large, with CARs averaging -13.54% within two hours after a stock’s first trading...

Using intraday 2015-2019 short sale data from CBOE and FINRA, we examine the intraday time patterns and information content of on-exchange and off-exchange shorting. Midday short sales and those near the open strongly and negatively predict the cross-section of stock returns at daily horizons...