Abstract

While it is not clear from Christensen, Hail, and Leuz (2016), the market abuse rules they examine are the same as in Cumming, Johan, and Li (2011), with a difference in focus on the date: Christensen et al. (2016) pick the date the regulations were signed into law, while Cumming et al. (2011) pick date the date the regulations were implemented with organizational agreements and computerized surveillance. Both papers study and find the exact same effect: regulatory change improves market liquidity. We explain the relative merits of the different approaches in this paper, and identify misleading statements in prior work.