Insider trading patterns

We revisit the information content of stock trading by corporate insiders with an expectation that opportunistic insiders will spread their trades over longer periods of time when they have a longer-lived informational advantage, and trade in a short window of time when their advantage is fleeting. Controlling for the duration of insiders' trading strategies, we find robust new evidence that both insiders' sales and purchases predict abnormal stock returns. In addition, we provide evidence that insiders attempt to preserve their informational advantages and increase their trading profits by disclosing their trades after the market has closed. When insiders report their trades after business hours, they are more likely to engage in longer series of trades, they trade more shares overall, and their trades are associated with larger abnormal returns. Finally, we show how accounting for these trading patterns sharpens screens for corporate insiders who trade on infor- mation.     

Insider trading and managerial incentives

We derive conditions under which permitting manager “insiders” to trade on personal account increases the equilibrium level of output and the welfare of shareholders. These increases are produced by two effects of insider trading. First, insider trading impounds information about hidden managerial actions into asset prices. This impounding of information allows shareholders to make better personal portfolio-allocation decisions. Second, allowing insider trading can induce managers to increase, on average, the correlation between their personal wealth and firm value beyond the level dictated by the employment relationship alone. This increased correlation increases managerial incentives. When these two effects are only weakly present, permitting insider trading harms shareholders, because insider trading reduces shareholder control over the performance–compensation relationship. In addition, when managerial effort incentives are high and corporate governance costs are low, managers may prefer insider-trading restrictions because such restrictions force shareholders to offer them a larger fraction of output through the employment relationship.     

Insider trading and risk aversion

This paper is a continuous time version of Holden and Subrahmanyam (Economics Letters 44 (1994) 181). The paper extends Kyle (Econometrica 53 (1985) 1315) by introducing risk aversion on the side of the monopolist informed trader and allows for the liquidity traders instantaneous demand to depend on cost of trading, as well as on the risk of the stock. The main result of the paper is that, in equilibrium, the price pressure decreases with time regardless of the elasticity of the liquidity demand function.     

Insider trading in takeover targets

We examine open market stock trades by registered insiders in about 3700 targets of takeovers announced during 1988–2006 and in a control sample of non-targets, both during an ‘informed’ and a control period. Using difference-in-differences regressions of several insider trading measures, we find no evidence that insiders increase their purchases before takeover announcements; instead, they decrease them. But while insiders reduce their purchases below normal levels, they reduce their sales even more, thus increasing their net purchases. This ‘passive’ insider trading holds for each of the five insider groups we examine, for all three measures of net purchases, and is more pronounced in certain sub-samples with less uncertainty about takeover completion, such as friendly deals, and deals with a single bidder, domestic acquirer, or less regulated target. The magnitude of the increase in the dollar value of net purchases is quite substantial, about 50% relative to their usual levels, for targets' officers and directors in the six-month pre-announcement period. Our finding of widespread profitable passive trading by target insiders during takeover negotiations points to the limits of insider trading regulation. Finally, our finding that registered insiders of target firms largely refrain from profitable active trading before takeover announcements contrasts with prior findings that insiders engage in such trading before announcements of other important corporate events, and points to the effectiveness of private over public enforcement of insider trading regulations.     

Insider trading and firm-specific return volatility

Roll (J Financ 43:541–566, 1988) argues that firm-specific stock return volatility may result either from informed trading or from noise trading that is unrelated to information. In this paper we provide evidence that insider purchases are inversely related to the idiosyncratic volatility of stocks. We also find that stock idiosyncratic volatilities are generally inversely related to future 6- and 12-month returns. Our results are primarily driven by the timing of insider sales rather than insider purchases. The results are consistent with an information-based explanation of firm-specific return volatility.     

Insider trading in credit derivatives

Insider trading in the credit derivatives market has become a significant concern for regulators and participants. This paper attempts to quantify the problem. Using news reflected in the stock market as a benchmark for public information, we find significant incremental information revelation in the credit default swap market under circumstances consistent with the use of non-public information by informed banks. The information revelation occurs only for negative credit news and for entities that subsequently experience adverse shocks, and increases with the number of a firm's relationship banks. We find no evidence, however, that the degree of asymmetric information adversely affects prices or liquidity in either the equity or credit markets.     

Insider trading in loss firms

This study investigates whether insiders in loss firms trade their company stock differentially around new loss and loss reversal earnings announcements. Research suggests that the likelihood of litigation influences managers' stock trading decisions prior to material events. I hypothesize and find that insiders reduce their net stock sales in a monotonic manner before a new loss announcement presumably to avoid improper trading allegations before bad news. This decrease is more pronounced if the new loss is the start of a multiple loss sequence. In contrast, there is no significant change in net trading patterns in the quarters prior to a loss reversal announcement irrespective of whether the loss reversal is the start of a single profit or multiple profit sequence indicating that insiders seem less concerned about legal implications when trading before good news. The results suggest that insiders in loss firms perceive asymmetric litigation risks to trading stock in the quarters before bad news relative to good news and act accordingly.     

Insider trading in rumored takeover targets

We examine insider trading surrounding takeover rumors in a sample of 1,642 publicly traded US firms. Using difference-in-differences regressions, we find that insider net purchases increase within the year prior to the first publication of a takeover rumor, particularly when rumor articles are either accurate (lead to a takeover announcement) or informative (provide substantial justification for the rumor's publication). Moreover, we find abnormal insider trading to be a significant predictor of takeover announcements occurring within the following year. Finally, passive net purchasing (i.e., selling less rather than buying more) is more pronounced among managing insiders than among non-managing insiders.     

Insider trading with correlation between liquidity trading and a public signal

We analyse a Kyle-type continuous-time market model in which liquidity trading is correlated with a noisy public signal that is released continuously. We show that, in contrast to the previous literature, Kyle's λ, the price sensitivity to the order flow, can even be non-monotonic, depending on the correlation structure. We also show that the introduction of an additional public signal does not necessarily improve the informational efficiency of the market, depending on the correlation.     

Insider employee stock option trading and stock prices

The question of which factors determine corporate bonds pricing is investigated by analysing the spreads of eurobonds issued by major G-10 companies during the 1991–2001 period. Three main results emerge from the analysis. First, bond ratings appear as the most important determinant of yield spreads, with investors’ reliance on rating agencies judgments increasing over time. Second, the primary market efficiency and the expected secondary market liquidity are not relevant explanatory factors of spreads cross-sectional variability. Finally, rating agencies adopt a different, ‘through the cycle’, evaluation criteria of default risk with respect to the forward looking one adopted by bond investors.     

Large shareholder trading and the complexity of corporate investments

This paper investigates how the presence of a large institutional shareholder affects the complexity of corporate investments. Our analysis is based on the observation that the blockholder’s planning horizon does not necessarily coincide with the time it takes for the market to correctly evaluate these investments. It demonstrates that this horizon mismatch creates an incentive for the large shareholder to manipulate the firm’s stock price. In equilibrium, corporate managers respond to these manipulation attempts by increasing the complexity of their investments. This in turn lowers the large shareholder’s incentive to collect costly information, which reduces price informativeness and exacerbates managerial myopia. Thus, our analysis identifies a new cost of block ownership resulting from an increased complexity of corporate investments.     

Insider and liquidity trading in stock and options markets

We analyze the introduction of a nonredundant option, whichcompletes the markets, and the effects of this on informationrevelation and risk sharing. The option alters the interactionbetween liquidity and insider trading. We find that the optionmitigates the market breakdown problem created by the combinationof market incompleteness and asymmetric information. The introductionof the option has ambiguous consequences on the informationalefficiency of the market. On the one hand, by avoiding marketbreakdown, it enables trades to occur and convey information.On the other hand, the introduction of the option enlarges theset of trading strategies the insider can follow. This can makeit more difficult for the market makers to interpret the informationcontent of trades and consequently can reduce the informationalefficiency of the market. The introduction of the option alsohas an ambiguous effect on the profitability of insider trades,which can either increase or decrease depending on parametervalues.     

Insider trading under trading ban regulation in China’s A-share market

This study examines the effects of China’s 2008 trading ban regulation on the insider trading of large shareholders in China’s A-share market.It finds no eviden...     

Insider trading as a signal of private information

There is substantial evidence that insider trading is presentaround corporate announcements and that this insider tradingis motivated by private information. Using real estate investmenttrusts that choose to reappraise themselves as our sample, weestablish that the appraisals contain information, but findno market response to the public announcement of this informationin these appraisals. We consider two possible explanations forthis inconsistency: the first that the appraisal informationis not highlighted in earnings reports and hence remains unobserved;and the second that insiders trade on the appraisal informationin the time that elapses between the appraisal and its publicannouncement We find strong support for the second hypothesis,with insiders buying (selling) after they receive favorable(unfavorable) appraisal news, especially for negative appraisals.We also find that positive (negative) appraisals and net insiderbuying (selling) elicit significant positive (negative) abnormalreturns during the appraisal period     

Insider trading in sequential auction markets with risk-aversion and time-discounting

We extend Kyle's [Kyle, A. S. 1985. “Continuous Auctions and Insider Trading.” Econometrica 53, 1315–1335] analysis of sequential auction markets to the case in which the insider is risk-averse and discounts her trading profits as her private information is long-lived. We see that time-discounting exacerbates the impact of risk-aversion on the optimal trading strategy of the insider. Ceteris paribus, a larger degree of risk-aversion or a smaller time-discount factor induces the informed agent to consume more rapidly her informational advantage increasing the liquidity and efficiency of the securities market.     

Insider trading and the long-run performance of new security issues

This paper uses insider trading around new security issues to provide evidence of managerial timing ability. I show that insider sales increase and purchases decrease prior to issues of information-sensitive securities (convertible debt and equity) by industrial firms. I then examine the relation between insider trading and subsequent stock returns. Although not all equity issues are motivated by overvaluation, those where managers sell prior to the issue are more likely to be. I find that industrial firms with abnormal insider selling underperform in the long run, whereas those with abnormal buying do not. There is no evidence of a relation between abnormal selling and future performance for utility offerings, however. Overall, the evidence is consistent with poor long-term performance being due to overvaluation.     

Insider trading law enforcement and gross spreads of ADR IPOs

Using American Depositary Receipt (ADR) IPOs from 34 countries during 1980-2004, we find that, on average, the enforcement of insider trading laws reduces the underwriter gross spread by 49-61 basis points, which is about 10-12% of the average gross spread for ADR IPOs. This relation is present regardless of whether issuers have a prior listing or whether issuers are from developed or emerging markets. The association becomes stronger for ADRs underwritten by less prestigious underwriters and for issuers that are involved in privatization. The political institutions in the issuers’ home markets also affect gross spreads.     

Insider trading activity,tenure length,and managerial compensation

In this study, insider trading activity is used as part of a managerial compensation structure. The wage structure changes with the tenure duration of the insider. Managers with shorter tenure rely more on insider profits as part of their compensation. On the other hand, managers with longer tenure execute insider transactions with lower profits. Different measurements of insider profits using calendar day returns of insider transactions, holding period returns for different horizons, or weighted average cumulative abnormal returns for the executive all lead to the same conclusion. The results are robust to various well-known empirical models, such as the CAPM model, the Fama and French (1993) three factor model, or the Carhart (1997) four factor model. Insider trading profits have increased in recent years overall, especially after the Securities and Exchange Commission (SEC) implementation of Rule 10b5-1 in 2000. Therefore, the design of a wage schedule incorporating insider trading activity has become more relevant.     

Insider trading,future earnings,and post-earnings announcement drift

This paper examines the association between insider trading prior to quarterly earnings announcements and the magnitude of the post-earnings announcement drift (PEAD). We conjecture and find that insider trades reflect insiders’ private information about the persistence of earnings news. Thus, insider trades can help investors better understand and incorporate the time-series properties of quarterly earnings into stock prices in a timely and unbiased manner, thereby mitigating PEAD. As predicted, PEAD is significantly lower when earnings announcements are preceded by insider trading. The reduction in PEAD is driven by contradictory insider trades (i.e., net buys before large negative earnings news or net sells before large positive earnings news) and is more pronounced in the presence of more sophisticated market participants. Consistent with investors extracting and trading on insiders’ private information, pre-announcement insider trading is associated with smaller market reactions to future earnings news in each of the four subsequent quarters. Overall, our findings indicate insider trading contributes to stock price efficiency by conveying insiders’ private information about future earnings and especially the persistence of earnings news.     

Insider trading in Hong Kong: Some stylized facts

This paper examines the characteristics and price movements of legal insider transactions in Hong Kong. Abnormal returns are analyzed for intensive trading, as well as for samples grouped by industry classification, firm size, book-to-market ratio, price–earnings ratio, and relative trading volume of the insider transactions. Results show that insiders are able to earn abnormal profits from both buying and selling activities. The magnitude of and duration for abnormal profits depend significantly on firm-specific and transaction-specific factors. We also document the persistence of abnormal returns associated with insider sales, while abnormal profits associated with insider purchases are concentrated in certain transactions.