美国的内线交易法

<正>从事股票交易的人都知道,他投资的公司任何可能影响股票价格的动态都是极其宝贵的,因为它或是带来丰厚的利润,或是造成巨大的损失。因此,股票持有人要随时把握公司的财政动态,及时买入或卖出股票。但是,如果有人利用工作之     

Investor Sophistication and Voluntary Disclosures

This paper studies voluntary disclosures in a model in which investors probabilistically become informed about whether a firm has received information. The firm's value is established via a first price, sealed bid, common value auction. The paper demonstrates that the threshold level determining whether the firm withholds or discloses information uniformly declines in the probability investors are informed. The paper also shows that, notwithstanding the risk-neutrality of investors, the expected selling price of the firm strictly decreases (increases) in the probability individual investors are informed when that probability is small (large). These results follow from winner's curse effects.     

Insider Trading and Earnings Management

Abstract:  This paper analyzes the relationship between earnings management and insider trading, specifically investigating whether discretionary accruals are related to insider trading and valuation. We find strong evidence of insiders managing earnings downward when buying and managing earnings upward when selling. On the marginal basis, value (high book-to-market value) firms manage their earnings upward compared to growth (low book-to-market value) firms, consistent with a signaling hypothesis. However, the opposite is true on the average basis, consistent with an opportunistic hypothesis.     

Financial Reporting and Supplemental Voluntary Disclosures

A standard result in the voluntary disclosure literature is that when the manager's private information is a signal correlated with the firm's liquidation value, mandatory disclosures substitute for voluntary disclosures. In this paper, we assume that the manager's private information complements the mandatory disclosure and show that the content and likelihood of a voluntary disclosure depend on whether the mandatory reports contain good or bad news. This different information asymmetry produces new, testable implications regarding the probability of and market reaction to voluntary disclosures. We also show that changes in mandatory disclosure regulations can have unintended consequences due to their effects on the manager's willingness to voluntarily provide supplemental disclosures.     

Mandatory and Voluntary Disclosures: Dynamic Interactions

Firms sometimes obtain soft private information about growth prospects along with hard information about current or past performance. In this environment, we find that optimizing disclosures over multiple periods yields nonlinear stock price reactions following both voluntary and mandatory disclosures. Further, we derive several predictions about distinct short‐run and long‐run effects of disclosures and nondisclosures on security prices. Under specified conditions, when the volatility of the firm's earnings increases, the average contemporaneous and prospective post‐mandatory‐disclosure market premia (for voluntary disclosures over nondisclosures) rise, while farther‐in‐future market discounts (for such voluntary disclosures) also become larger. Our analysis moreover predicts that both the disclosure probability and the information content of nondisclosures can increase in the persistence of earnings.     

Intertemporal Dynamics of Corporate Voluntary Disclosures

While empirical evidence alludes to the intertemporal nature of corporate voluntary disclosures, most of the existing theory analyzes firms' voluntary disclosure decisions within single‐period settings. Introducing a repeated, multiperiod, disclosure setting, we study the extent to which firms' strategic disclosure behavior in the past affects their prosperity to provide voluntary disclosures in the future. Our analysis demonstrates that by voluntarily disclosing private information firms make an implicit commitment to provide similar disclosures in the future, and therefore are less willing to voluntarily disclose information in the first place. This effect is expected to be of larger magnitude for firms (1) with a long history of absence of voluntary disclosures and an impressive past operating performance, or (2) that operate in a relatively stable and predictable business and information environment, or (3) whose managers have a long time horizon and a high degree of risk aversion.     

Optimal Contracting and Insider Trading Restrictions

Restrictions on trading by insider agents are analyzed using an optimal contracting framework. Prohibition of insider trading is shown to be Pareto preferred if, and only if, a revelation or moral hazard problem exists. If prohibition of insider trading is valuable, then trade registration with a delay is shown to be as valuable as complete prohibition. Short selling restrictions, however, are generally of less value than complete prohibition. Finally, regulation of insider agent trading by governmental institutions and/or professional associations is discussed.     

内幕交易监管与监管困境研究综述

各国对内幕交易的监管基本采取立法的形式，许多学者都探讨了实施内幕交易监管的有效性以及监管效率问题。本文对相关文献进行了梳理，发现从内幕交易监管有效性的纵向比较分析，内幕交易监管并不能达到预期的效果；从横向比较分析，内幕交易监管越严格，越有利于降低内幕交易程度。总体而言，内幕交易监管是必要与相对有效的。因交易者策略与量价甄别指标的主观性而产生了监管困境，降低了监管效率。但是监管总体上可以带给市场的效益高于成本，那么内幕交易监管的实施与不断完善是非常有必要的。     

Insider Trading in the OTC Market

In this paper, we examine the profitability of insider trading in firms whose securities trade in the OTC/NASDAQ market. Although the evidence suggests timing and forecasting ability on the part of insiders, high transaction costs (especially bid-ask spreads) appear to eliminate the potential for positive abnormal returns from active trading. By implication, outside investors who mimic the trading of insiders are also precluded from earning abnormal profits. In addition, we provide evidence on the determinants of insiders' profits. The data suggest that insiders closer to the firm trade on more valuable information than insiders removed from the firm.     

Voluntary Environmental Disclosures by Large UK Companies

Abstract:  This paper examines the patterns in voluntary environmental disclosures made by a sample of large UK companies. The analysis distinguishes between the decision to make a voluntary environmental disclosure and decisions concerning the quality of such disclosures and examines how each type of decision is determined by firm and industry characteristics. We find that larger, less indebted companies with dispersed ownership characteristics are significantly more likely to make voluntary environmental disclosures, and that the quality of disclosures is positively associated with firm size and corporate environmental impact. We find significant cross-sector variation in the determinants of both the participation and quality decisions. Furthermore, the manner of this variation differs between the two.     

Voluntary Disclosures,Corporate Control,and Investment

We examine the valuation and capital allocation roles of voluntary disclosure when managers have private information regarding the firm’s investment opportunities, but an efficient market for corporate control influences their investment decisions. For managers with long‐term stakes in the firm, the equilibrium disclosure region is two‐tailed: only extreme good news and extreme bad news is disclosed in equilibrium. Moreover, the market’s stock price and investment responses to bad news disclosures are stronger than the responses to good news disclosures, which is consistent with the empirical evidence. We also find that myopic managers are more likely to withhold bad news in good economic times when markets can independently assess expected investment returns.     

自愿性信息披露:信息租金与管制

自愿性信息披露是解决信息问题的重要手段, 对间接信息租金的追逐是经营者自愿披露信息的核心动机。单纯受利益驱使的自愿性信息披露必然存在一些问题, 因而有必要对自愿性信息披露进行有效的管制。建立基于声誉的经理人市场和法律事后惩罚机制, 有助于保障自愿性信息披露的信息质量。     

浅析单位内幕交易违法的认定与处罚

近年,单位作为主体从事内幕交易的案例呈增加之势。本文结合行政执法与刑事司法实践,结合近年典型单位内幕交易案例,并借鉴海外监管查处经验,着重讨论了单位内幕交易认定的一些疑难法律问题,诸如是否将单位作为违法主体以及是否处罚、如何认定单位知悉与利用内幕信息、如何区分单位内幕交易行为与个人内幕交易行为等问题。     

内幕交易理论的普通法基础

本文以美国最高法院的重要判例为主线,讨论内幕交易的"特定事实"学说、经典理论和盗用理论,分析这些理论的普通法基础及其演变过程,以图说明内幕交易法的移植是一件非常困难的事,各国(地区)只有以自己的基本法律、执法机制和司法体制为依归,才能发展出合用的内幕交易法.     

The Persistence of Opportunistic Insider Trading

We study the drivers of persistent insider trading profitability by examining the trades of insiders whose past trades have been profitable. We find that the current transactions of these persistently profitable (PP) insiders better predict firm performance than those of other insiders. The relative abnormal performance is more pronounced for trades of insiders who are managers rather than large shareholders or unaffiliated insiders and for trades in firms with weaker governance and greater information asymmetry. The trades of PP insiders also better predict earnings surprises, major corporate news, and analyst revisions. Collectively, these results indicate that PP insider transactions provide valid signals regarding future firm performance and that persistence in profitability is driven by informational advantages.     

The World Price of Insider Trading

The existence and the enforcement of insider trading laws in stock markets is a phenomenon of the 1990s. A study of the 103 countries that have stock markets reveals that insider trading laws exist in 87 of them, but enforcement—as evidenced by prosecutions—has taken place in only 38 of them. Before 1990, the respective numbers were 34 and 9. We find that the cost of equity in a country, after controlling for a number of other variables, does not change after the introduction of insider trading laws, but decreases significantly after the first prosecution.     

Insider Trading in Financial Signaling Models

We study the impact of voluntary trade by the manager. We find that, in contrast to standard signaling models, an action is good news for some firms and bad news for others, depending on observable characteristics of the firm, its managers, and their compensation plans. Further, voluntary trade eliminates separating equilibria and thus the possibility of exactly inferring the manager's private information. This may cause the manager to take inefficient actions so as to earn trading profits. Such undesirable behavior can be more effectively constrained by compensation contracts based on phantom shares or nontradeable options instead of large stockholdings.     

Voluntary Causal Disclosures: Tendencies and Capital Market Reaction

In this study, we provide empirical evidence on whether voluntarily disclosed causal attributions made in management earnings forecasts are credible by investigating the conditions under which such attributions are made and the extent to which security price responses are associated with attribution existence. We find that causal attributions are more likely to be made when forecast news is bad (relative to good), and that the type of attribution made is more likely to be external (internal) for bad (good) forecast news. Incorporating the existence and type of attribution into models that explain announcement period three-day cumulative abnormal returns yields significant effects for attribution incidence and type after controlling for unexpected earnings and forecast type (e.g., point, range, etc.). Consistent with the idea that attributions enhance the credibility or precision of management forecasts, attribution disclosure enhances price reactions per dollar of unexpected earnings conveyed in a management forecast.     

上市公司内部人亲属股票交易行为研究

中国的《证券法》等法律法规禁止内部人短线交易,并设置了内部人禁止股票买卖的敏感期,但内部人亲属不受此限制。本文对深圳证券交易所2007年5月至2010年5月的内部人亲属股票交易数据分析发现:(1)上市公司的内部人亲属对内部人任职企业的股票交易次数已经远远多于内部人自身的交易次数;(2)内部人亲属的交易存在很多的短线交易行为与敏感期交易行为;(3)内部人亲属股票交易整体而言能够获得超额收益;(4)短线交易与敏感期交易有助于内部人亲属获得超额收益;(5)董事长或总经理的亲属获得的收益比其他内部人亲属更高。据此,本文认为证券交易监管机构需要关注内部人亲属股票交易行为,尤其警惕内部人亲属交易可能成为规避内部人交易管制的替代方式。