Insider Trading with a Random Deadline under Partial Observations:Maximal Principle Method

For a revised model of Caldentey and Stacchetti(Econometrica,2010)in continuous-time insider trading with a random deadline which allows market makers to observe some information on a risky asset,a closed form of its market equilibrium consisting of optimal insider trading intensity and market liquidity is obtained by maximum principle method.It shows that in the equilibrium,(i)as time goes by,the optimal insider trading intensity is exponentially increasing even up to infinity while both the market liquidity and the residual information are exponentially decreasing even down to zero;(ii)the more accurate information observed by market makers,the stronger optimal insider trading intensity is such that the total expect profit of the insider is decreasing even go to zero while both the market liquidity and the residual information are decreasing;(iii)the longer the mean of random time,the weaker the optimal insider trading intensity is while the more both the residual information and the expected profit are,but there is a threshold of trading time,half of the mean of the random time,such that if and only if after it the market liquidity is increasing with the mean of random time increasing.

Impact of macroeconomic policy uncertainty on opportunistic insider trading

The macroeconomic policy environment affects the internal governance of microenterprises,which may provide opportunities for management to benefit from stock sales while decreasing its motivation to manipulate stock transactions.Using a sample of Chinese A-share listed companies from 2007 to2018,we study the impact of macroeconomic policy uncertainty on opportunistic insider trading.The results show that macroeconomic policy uncertainty helps restrain the opportunistic trading of shares held by management.When macroeconomic policies are uncertain,enterprises improve their internal governance.Furthermore,strengthening equity governance helps reduce management’s opportunistic use of the uncertainty of the policy environment,highlighting the advantageous effect of macroeconomic policy uncertainty and helping regulators standardize managerial behavior and promote the governance effect of macroeconomic policy.

Probability of informed trading during the COVID‑19 pandemic:the case of the Romanian stock market

Using data from the Bucharest Stock Exchange,we examine the factors influencing the probability of informed trading(PIN)during February—October 2020,a COVID-19 pandemic period.Based on an unconditional quantile regression approach,we show that PIN exhibit asymmetric dependency with liquidity and trading costs.Furthermore,building a customized database that contains all insider transactions on the Bucharest Stock Exchange,we reveal that these types of orders monotonically increase the infor-mation asymmetry from the 50th to the 90th quantile throughout the PIN distribution.Finally,we bring strong empirical evidence associating the level of information asym-metry to the level of fake news related to the COVID-19 pandemic.This novel result suggests that during episodes when the level of PIN is medium to high(between 15 and 50%),any COVID-19 related news classified as misinformation released during the lockdown period,is discouraging informed traders to place buy or sell orders condi-tioned by their private information.

Asymmetric Information, Heterogeneous Prior Beliefs and Market Regulation

This paper studies the trading behavior of an irrational insider and its influence on the market equilibrium in the presence of market regulation.We find that the market with only one insider with private information is almost close to a strong efficient market,under the condition of market regulation.In the equilibrium,the probability of the insider being caught trading with private information is zero,which shows that the reasonable behavior of the regulator is to essentially give up regulation.But the market efficiency and the irrational trader’s trading intensity all greatly improve because of the existence of the market regulation.

The Impact of Initial Public Offering Lockup Expirations on Liquidity:Evidence from Chinese Stock Market

Previous empirical evidence on the liquidity effect to the lockup expiration is mixed. A sample from Chinese listed firms is adopted and contributes to better understand this effect in emerging markets. The spread and illiquidity significantly increases around lockup expiration in China. Furthermore, the liquidity reaction to firms' disclosure quality is explicitly related. The results confirm that higher disclosure quality is significantly associated with lower abnormal spread and illiquidity impact. The effect of lockup expiration shares on liquidity proxies differs in firm disclosure quality. Identifying the factors affecting liquidity around such events may help regulators develop policies to provide investors with greater confidence in their investments.