The daily and intradaily effects of UK director dealings on stock trade price and non-price characteristics
Abstract
This thesis proposes a new classification of insider dealings based on their qualitative
characteristics and their execution strategy. First, this thesis finds that the ‘stated
purpose’ characteristic reported in the announcements of insider dealings at the London
Stock Exchange helps distinguishing between discretionary and non-discretionary
dealings, and that the former, especially discretionary sales, are associated with higher
abnormal returns. Second, this thesis introduces a new algorithm for matching insider
dealing announcements to actual executed trades with a much higher detection rate
compared to past papers. The first analysis uses the detected trades to identify intraday
stealth trading and investigates how this affects subsequent pricing. The results indicate
that stealth-trading practices are associated with weaker and longer-lived information
signals. When directors face shorter-lived negative information, they opt not to trade
stealthily and execute their intended sale in one large order. In addition, their holding
status helps to explain why they are rushing to sell shares when they are in the possession
of negative information. Nowadays, UK directors tend to have large shareholding
percentages, as well as high potential ownership from future stock rewards. They,
therefore, rush to sell shares but not rush to buy shares. The second analysis uses standard
measures of adverse selection costs to investigate the level of information asymmetry on
the days of director trades. These adverse selection measures show that there are higher
levels of information asymmetry and adverse selection costs on days with director
upstairs informed trades. Some upstairs trades are subject to a pre-trade transparency
requirement while others are not. The third analysis investigates the price and non-price
impacts around director trades with a focus on how pre-trade transparency of director
trades affects the market ability in uncovering the implied private information. The
analysis shows evidence that the pre-trade transparency requirement helps the market
uncover different levels of implied information by UK director trades. The lack of pretrade transparency reduces the ability of the market to incorporate the implied private
information. This stresses out the importance of transparency regulatory requirements.