The underlying shares of some American Depositary Receipts (ADRs) can be short sold in their home markets, and others cannot. This institutional feature offers a unique opportunity to investigate the relation between short selling and price discovery. We hypothesize and confirm that ADR short selling on a U.S. exchange is more informative when the ADRs’ underlying shares cannot be short sold in the home market. These and related results suggest that short sellers make a significant contribution to price discovery. Short sellers’ trading activity, representing more than 20% of total ADR share volume, increases the benefits of cross-listing on U.S. exchanges.