A reader commented and asked: “I searched your site for ‘insider’ and found very little investigation of a relationship between insider buys and stock price movement. Is this an area you could look at, classify and present to readers?”
See the “Buybacks-Secondaries” category for research on insider trading conducted at the corporate level. See also the following specific research summaries:
“Using Insider Trading to Find Informed Short Sellers”
“Finding the Sources and Methods of Financial Expertise in a Haystack”
Much of the research on individual insider trading examines laws, regulations and restrictions on such trading, and violations thereof. For research on insider trading as a predictive tool, see the following heavily downloaded papers derived from a search of the Social Science Research Network for “insider” in the title or abstract:
From March 2008, “Insider Trading Before Accounting Scandals”: “We examine insider trading in a sample of over 500 firms involved in accounting scandals revealed by earnings-decreasing restatements, and in a control sample of non-restating firms. Managers are less likely to trade before accounting scandals than before other major corporate events such as takeovers or bankruptcies. Managers who sell stock while earnings are misstated potentially commit two crimes, earnings manipulation and insider trading, and their selling increases investor scrutiny and the likelihood of the manipulation being revealed. We analyze open-market stock transactions of five groups of corporate insiders: top management, top financial officers, all corporate officers, board members, and blockholders. We examine their purchases, sales and net sales during the misstated period and a pre-misstated period, using a difference-in-differences approach. Using several measures of the level of insider trading, we estimate cross-sectional regressions that control for other determinants of the level of insider trading. For the full sample of restating firms, we find weak evidence that top managers of misstating firms sell more stock during the misstated period than during the pre-misstated period, relative to the control sample. But in a number of sub-samples where insiders had greater incentives to sell before the revelation of accounting problems, we find strong evidence that top managers of restating firms sell substantially more stock during the misstated period. These findings suggest that managers’ desire to sell their stockholdings at inflated prices is a motive for earnings manipulation. Our finding that insiders brazenly trade on a crime for which they are potentially culpable suggests that insider trading is more widespread in the market than has been found in the prior literature.”
From May 2006, “Insider Trading and Voluntary Disclosures”: “We hypothesize that insiders strategically choose disclosure policies and the timing of their equity trades to maximize trading profits, subject to the litigation costs associated with disclosure and insider trading. Accounting for endogeneity between disclosures and trading, we find that when managers plan to purchase shares, they increase the number of bad news forecasts to reduce the purchase price. In addition, this relation is stronger for trades initiated by chief executive officers than those initiated by other executives. Confirming this strategic behavior, we find that managers successfully time their trades around bad news forecasts, buying fewer shares beforehand and more afterwards. We do not find that managers adjust their forecasting activity when they are selling shares, consistent with higher litigation concerns associated with insider sales. Overall, our evidence suggests that insiders do exploit voluntary disclosure opportunities for personal gain, but only selectively, when litigation risk is sufficiently low.”
From September 2005, “Insider Trading, News Releases and Ownership Concentration”: “This paper investigates the market’s reaction to UK insider transactions and analyzes whether the reaction depends on the firm’s ownership. There are three major findings. First, differences in regulation between the UK and US, in particular the speedier reporting of trades in the UK, may explain the observed larger abnormal returns in the UK. Second, ownership by directors and outside shareholders has an impact on the abnormal returns. Third, it is important to adjust for news released before directors’ trades. In particular, trades preceded by news on mergers & acquisitions and CEO replacements contain significantly less information.”
From July 2005, “Stock Market Anomalies: What Can We Learn from Repurchases and Insider Trading?”: “We examine whether managers’ trading decisions (both at a firm and personal level) are correlated with trading strategies suggested by the operating accruals and the post-earnings announcement drift (SUE) anomalies. We discuss advantages and disadvantages of the use of managerial trading activity to infer managers’ private valuation about their own securities. Our results provide corroborative evidence for the accruals anomaly, i.e., managers’ repurchase and insider trading behavior varies consistently with the information underlying the operating accruals trading strategy. On the other hand, we do not find corroborative evidence for the SUE anomaly.”
From April 2005, “How Informative are Analyst Recommendations and Insider Trades?”: “This study jointly evaluates the informativeness of insider trades and analyst recommendations. We show that the two activities often generate contradictory signals. Insiders in aggregate buy more shares when their firm’s stock is unfavorably recommended or downgraded by analysts than when it is favorably recommended or upgraded. This result is robust to various controls such as varying degrees of analyst coverage, firm size, book-to-market ratios, and stock price momentum. We find that analyst recommendations affect insider trading decisions, but not vice versa. Our further analysis shows that insider trading is informative when signaling positive information, and analyst recommendations are informative when conveying negative information. The overall results imply that corporate insiders and financial analysts do not substitute each other’s informational role in the financial market.”
From January 2004, “Insider Trading and Incentives to Manage Earnings”: “This paper evaluates two hypotheses about the relation between insider selling and earnings management in periods preceding poor corporate performance. Consistent with our litigation avoidance hypothesis, we provide evidence that managers manage earnings upwards after they have engaged in abnormally high levels of insider selling. In contrast, we find no support for the pump and dump hypothesis of earnings being managed before managers sell their equity. Our findings indicate insider trading provides managers with incentives to subsequently manage earnings upward, to distance their selling from the revelation of bad news and reduce the likelihood of reputation, employment, and litigation losses. We show these incentives co-exist and complement incentives to avoid default in a sample of 462 firms that experience technical default in 1983-1997. Our findings suggest that investors and those with oversight authority (e.g., boards of directors, auditors, and regulators) consider monitoring prior rather than contemporaneous insider-trading activity as a part of their corporate governance practices.”
From May 2003, “Estimating the Returns to Insider Trading: A Performance-Evaluation Perspective”: “This paper uses performance-evaluation methodology to estimate the returns earned by insiders when they trade their company’s stock. Our methods are designed to estimate the returns earned by insiders themselves and thereby differ from the previous insider-trading literature, which focuses on the informativeness of insider trades for other investors. We find that insider purchases earn abnormal returns of more than 6 percent per year, and insider sales do not earn significant abnormal returns. We compute that the expected costs of insider trading to non-insiders are about 10 cents for a $10,000 transaction.”
From January 2003, “Do Insider Trades Reflect Superior Knowledge about Future Cash Flow Realizations?”: “This paper examines whether insider trades reflect the insiders’ superior knowledge of future cash flow realizations, as proxied by the firm’s future return and earnings performance. We find strong evidence that insider trades are positively associated with the firm’s future earnings performance. This relation is shown to be incremental to the book-to-market and past return relations documented in Rozeff and Zaman (1998), suggesting that insiders trade on both transitory security misvaluation and private information about future cash-flow payoffs. We find that insider trading behavior within each book-to-market portfolio varies with the horizon of the subsequent earnings news. Insider purchases are significantly positively related to next year’s earnings news across all book-to-market portfolios, while the sign of the relation between insider purchases and contemporaneous earnings is negative (positive) for glamour (value) firms. Finally, we show that the relation between insider trades and future earnings performance is amplified (attenuated) as the likely ex ante benefits (costs) to trading on financial performance information increase.”
From March 2002, “What Insiders Know About Future Earnings and How They Use It: Evidence From Insider Trades”: “This paper provides evidence that insiders possess, and trade upon, knowledge of specific and economically-significant forthcoming accounting disclosures as long as two years prior to the disclosure. Stock sales by insiders increase three to nine quarters prior to a break in a string of consecutive increases in quarterly earnings. Insider stock sales are greater for growth firms, before a longer period of declining earnings, and when the earnings decline at the break is greater. Consistent with avoiding an established legal jeopardy, there is little abnormal selling in the two quarters immediately prior to the break.”
From June 2001, “Insider Trading, Earnings Quality, and Accrual Mispricing”: “The paper provides evidence that the signal contained in insiders’ trading behavior is useful in making refined assessments of earnings quality, and informative about the valuation implications of accruals. We find that income-increasing accruals and unexpected accruals have lower (higher) persistence when managers engage in abnormal selling (buying) suggesting that insider trading information is useful in assessing the quality of the non-cash components of earnings. We show that the accrual mispricing phenomenon observed in previous work is largely due to the mispricing of positive accruals. We find that investors price all positive accruals as if they were informative and that a subset of positive accruals is correctly priced. That is, (1) investors correctly price positive accruals that are likely to be informative because concurrently insiders engage in abnormal buying, and (2) investors price all positive accruals the same independently of insider trading. We find that the extent of the mispricing is greater when positive accruals occur concurrently with abnormal selling relative to cases where there is no trading. The extent of the mispricing and the magnitude of the one-year ahead returns (14.7 to 22 percent) to a trading strategy based on positive accruals and abnormal selling suggests that these accruals arise from opportunistic earnings management that is successful in misleading investors. By contrast, the smaller positive accrual mispricing when there is no insider trading is more likely related to either the complexity of the firms’ accrual generating process (Thomas and Zhang (2001) or to earnings fixation (Sloan 1996). Our evidence thus suggests that opportunistic earnings management is a partial explanation for the accrual mispricing phenomenon.”
