We show that demand effects generated by institutional frictions can influence systematic return predictability patterns in stocks and mutual funds. Identification relies on a reform to the Morningstar rating system, which we show caused a structural break in style-level positive feedback trading by mutual funds. As a result, momentum-related factors in stocks, as well as performance persistence and the “dumb money effect” in mutual funds, experienced a sharp decline. Consistent with the proposed channel, return predictability declined right after the reform, was limited to the U.S. market, and was concentrated in factors and mutual funds most exposed to the mechanism.

Cumulative abnormal returns (CARs) computed around acquisition announcements are widely considered to be market‐based assessments of expected value creation. We show, however, that announcement returns do not correlate with commonly used and new measures of ex post outcomes. A simple characteristics‐based model using standard information known at the announcement date can predict these outcomes reasonably well, yet CAR even fails to capture the predictions from this model. Evidence suggests that information about the stand‐alone acquirer dominates CAR, making it virtually impossible to extract deal‐related information. We conclude that CAR is an unreliable measure of expected value creation.

We provide evidence suggesting that some hedge funds manipulate stock prices on critical reporting dates. Stocks in the top quartile of hedge fund holdings exhibit abnormal returns of 0.30% on the last day of the quarter and a reversal of 0.25% on the following day. A significant part of the return is earned during the last minutes of trading. Analysis of intraday volume and order imbalance provides further evidence consistent with manipulation. These patterns are stronger for funds that have higher incentives to improve their ranking relative to their peers.