Using cross-country data on trading by international mutual funds, I find that firms
with more opaque information environments, as captured by firm- and country-level
measures of the availability of financial reporting information, experience more
privately informed trading by institutional investors. The association between firmlevel
opacity and informed trading is most pronounced where country-level disclosure
infrastructures are less developed and for those investors for whom the incentives and
opportunities to acquire private information are greatest. A difference-in-differences
analysis of the returns earned by institutions in opaque stocks suggests that this
information advantage is economically significant.