The impact of insider trading on analyst coverage and forecasts
Authors: He Guanming , Marginson David 
Published: June 2020

Purpose
The purpose of this study is to examine the effect of insider trading on analyst coverage and the properties of analyst earnings forecasts. Given the central role of analysts for information diffusion in stock markets, advancing understanding of the role insider trades may play in analyst coverage and forecasts, especially in the context of a changing legal environment (e.g. the implementation of Regulation Fair Disclosure [Reg FD]), should be a worthy goal.

Design/methodology/approach
To address the research questions, the authors run regressions in which the authors identify and control for as many possible determinants of analyst coverage and forecasts (e.g. firm size, information asymmetry and earnings performance) that are correlated with insider trades. To alleviate endogeneity concerns, the authors use three approaches. First, the authors extend the sample period to the post-Reg-FD period in which managers are not allowed to provide private information to financial analysts. Second, the authors measure analyst coverage in a window that is lagged by insider trades. Third, the authors employ firm-fixed-effects regressions in all the multivariate tests. Finally, following Larcker and Rusticus (2010), the authors conduct the impact threshold for a confounding variable test to assure that all regression analyses are indeed immune to the potential correlated-omitted-variable bias.

Findings
The authors find that the level of analyst coverage is positively related to the intensity of insider trades and that analyst coverage is more strongly associated with insider purchases than with insider sales. The authors also find that the positive association between analyst coverage and insider trades is less pronounced after the passage of Reg FD. Further investigations reveal that analysts revise their earnings forecasts upward following insider purchases, the informativeness of analyst forecast revisions significantly increases following insider purchases and optimistic bias in analyst forecast revisions is reduced as a result of insider purchases; the authors do not find similar evidence for insider sales.

Research limitations/implications
A large body of insider trading literature (Johnson et al., 2009; Badertscher et al., 2011; Thevenot 2012; Skaife et al., 2013; Billings and Cedergren 2015; Dechow et al., 2016) provides evidence that insiders actively trade on their private information, such as their foreknowledge of price-relevant corporate events. This literature suggests that insider trades are potentially value-relevant and are informative about a firm’s future prospects. However, less research attention has been paid to investigating how insider trades might affect market participants’ (especially sophisticated participants’) behavior. This study contributes to understanding the role that insider trading may play in shaping analyst behavior.

Practical implications
Prior research (Frankel and Li, 2004; Lustgarten and Mande, 1995; Carpenter and Remmers, 2001; Seyhun, 1990) maintains that insider sales are less informative about a firm’s future prospects than are insider purchases because insider sales might take place for the liquidity and diversification purposes. By probing the stock price responses to insider selling activities, Lakonishok and Lee (2001), Jeng et al. (2003) and Fidrmuc et al. (2006) infer that insider selling is not informative about future firm performance. However, for such an inference, the authors cannot rule out the possibility that insider sales do convey value-relevant information, but the stock market does not react correctly to such trading information (Beneish and Vargus, 2002). Because the authors focus on examining analysts’ responses to insider sales, and analysts are supposed to be sophisticated in information processing, this study adds more compelling evidence for the notion that insider sales convey less information about a firm’s future prospects than do insider purchases.

Social implications
There is an ongoing debate about the benefits and drawbacks of insider trading. Opponents of insider trading view insider trades as inequitable and immoral and assert that restricting insider trades curbs resource misallocation and benefits the whole society. Proponents contend that insider trading accelerates the price discovery process, increases market efficiency (Leland, 1992; Bernhardt et al., 1995; Choi et al., 2016) and may even play a role in rewarding and motivating executives (Roulstone, 2003; Denis and Xu, 2013). The authors add to this debate by documenting that insider trading increases the amount of information valuable to analyst research activities and helps enhance analyst services.

Originality/value
To the best of the authors’ knowledge, this study is the first to offer firm-level evidence of a positive association between insider trades and analyst coverage. By accounting for the post-Reg-FD regime, this paper is also the first to provide evidence on how analysts, in the absence of access to management’s private information because of the regime change by Reg FD, react to insider trades.