How does the trading behaviour of institutional money managers affect stock prices? In this paper we document a robust relationship between the net trade patterns of institutional money managers and long term equity returns. Examining quarterly data on US institutional holdings from 1983 to...

This paper shows that the systematic risk (or "beta") of individual stocks increases by an economically and statistically signi…cant amount on days of firm-specific news announcements, and reverts to its average level two to five days later. We employ intra-daily data and recent advances in...