This paper analyzes factors that affect the exit and expansion of U.S. petroleum refineries using plant-level capacity data from 1947 to 2013. We find that larger refineries are less likely to close and that refineries owned by a multi-plant firm are more likely to close. If a multi-plant firm closes a refinery, it is likely to close its smaller refineries. In contrast to previous literature, we find weak evidence that refineries owned by firms with higher market shares are less likely to close. In specifications with more control variables, this relationship is statistically insignificant.