Note(s): This table reports the results of pooled OLS DID regression on the post-acquisition stock performance for the pilot and the control firms over the periods before and during Regulation SHO's pilot program. We use the CAR relative to a size and MB ratio benchmark during a time window of 36 months after the deal completion as the measure of post-acquisition performance

$CARi,t=α0+β1Piloti×Duringt+β2Piloti+β3Duringt+εi,t.$

CAR_i,t is firm i's CAR relative to a size and MB ratio benchmark during a time window of 36 months after the deal completion. Pilot_i equals one if firm i belongs to the pilot group and zero otherwise. During_t is a dummy variable that equals one if the year is during the During period (2005 to 2007). We use three different samples. In the first sample, we use all deals. In the second sample, we first follow Loughran and Vijh (1997) to exclude the observations that occurred within three years of a previous acquisition by the same firm. We then follow Moeller et al. (2005) and Harford et al. (2012) and require the deal value to be more than 1 million and worth at least 1% of the acquirer's market value of assets. In the third sample, we also exclude the observations that occurred within three years of a previous acquisition by the same firm and then use a higher deal value criterion than that used in the second sample. Consistent with Duchin and Schmidt (2013), we require that the deal value be more than 10 million and worth at least 5% of the acquirer's market value of assets. We adjust the standard errors to be heteroscedasticity-consistent. ^***, ^**, and ^* denote significance at the 1%, 5%, and 10% level, respectively