Evidence of Informed Trading Prior to Earnings Announcements

This study examines transactions in stocks during the thirty trading days prior to earnings announcements. Using two methodologies, we find evidence of informed trading for initiators of large transactions (presumably institutions) but not for initiators of small transactions (presumably individuals). Specifically, we find that, relative to a control period, initiators of large transactions tend to buy (sell) stocks prior to earnings announcements that exceed (fall short of) analyst’ forecasts. In addition, the fraction of total stock price movement that occurs on large transactions is substantially higher during the pre-announcement period than during the control period. Results of both tests suggest, contrary to previous research, that some large traders have and use superior private information prior to large earnings surprises

Market Share Growth and Stock Returns

We find a negative relationship between market share growth and subsequent stock returns, three- and four-factor alphas. We report the potential explanatory role of market share growth in explaining subsequent average monthly stock returns. High (Low) market share growth firms report good (poor) operating performance and positive (negative) SUEs in the quarter in which market share growth is measured and investors overact to that good (bad) news. However, high (low) market share growth firms experience decrease (increase) in operating performance and SUEs in the subsequent quarters resulting in corrections in investors’ expectations and subsequent lower (higher) stock returns

Intraday Behavior of Stock Prices and Trades around Insider Trading

Our evidence indicates that insiders’ trades provide significant new information to market participants and they are incorporated more fully in stock prices as compared to noninsiders’ trades. We find that market professionals do not front-run insiders’ trades. Both insiders’ purchases and sales result in significant contemporaneous and subsequent price impact, while sales by large shareholders result in a contemporaneous stock price decline that is subsequently reversed. The arrival of insider purchases reverse the prevailing negative order imbalances from third party trades and lead to piggy-backing by market professionals resulting in subsequent market purchase orders as well as stock price increases.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79103/1/j.1755-053X.2009.01075.x.pd