Short-Selling Prior to Earnings Announcements

This paper examines short‐sales transactions in the five days prior to earnings announcements of 913 Nasdaq‐listed firms. The tests provide evidence of informed trading in pre‐announcement short‐selling because they reveal that abnormal short‐selling is significantly linked to post‐announcement stock returns. Also, the tests indicate that short‐sellers typically are more active in stocks with low book‐to‐market valuations or low SUEs. The levels of pre‐announcement short‐selling, however, mostly appear to reflect firm‐specific information rather than these fundamental financial characteristics. We believe that these results should encourage financial market regulators to consider providing more extensive and timely disclosures of short‐selling to investors.     

Does short selling improve stock price efficiency and liquidity? Evidence from a natural experiment in China

China introduced short selling for designated stocks in March 2010. Using this important policy change as a natural experiment, we examine the effect of short selling on stock price efficiency and liquidity. We show that the introduction of short selling significantly improves price efficiency, as measured by the differences in individual stock responses to market returns and the delay in price adjustments. Short selling also enhances stock liquidity, as measured by bid-ask spread and Amihud [2002. ‘Illiquidity and Stock Returns: Cross-section and Time-series Effects.’ Journal of Financial Markets 5: 31–56] illiquidity measure; and reduces stock volatility. Overall, our results suggest that short selling helps to stabilize asset prices, provides additional liquidity and improves market quality, even in an emerging economy with a less developed stock market than that in the US and Europe.     

Short‐selling constraints and corporate payout policy

This study shows that managers adjust corporate payout policies to counteract intensified short‐selling pressures following the removal of a short‐selling constraint. We use a controlled experiment, the Regulation SHO pilot program, to find that changing the short‐selling rule brings small companies to increase cash dividends, but not to repurchase more shares. Because paying dividends is costly, it is acknowledged as a more reliable signal of stock undervaluation than share repurchase. While our evidence suggests that companies select this payout strategy to deter predatory short sellers, it also shows that a short‐selling activity has a causal effect on corporate payout decisions.     

Short-sale refinancing and price adjustment speed to bad news: Evidence from a quasi-natural experiment in China

Short selling may accelerate stock price adjustment to negative news. However, the literature provides mixed evidence for this prediction. Using short-sale refinancing and a staggered difference-in-differences (DID) model, this paper explores the effect of short selling on stock price adjustment. Our results show that (1) short-sale refinancing improves the speed of stock price adjustment to negative news. This result holds after we control for endogeneity. (2) The positive relationship between short-sale refinancing and stock price adjustment speed is significant in subsamples of stocks with higher earnings management or lower accuracy of analyst forecasts, indicating that firms with more opaque information are more likely to be targeted by short sellers. In subsamples of stocks with a higher ownership concentration or lower ownership by institutional investors, short selling is more likely to increase the speed of stock price adjustment, indicating that ownership structure may influence negative news mining. (3) As short-sale refinancing exacerbates the absorption of bad news by stock prices, it increases crash risk. This study enriches the research on the economic consequences of short selling and provides empirical evidence supporting regulations on short selling in China.     

Effect of the ban on short selling on market prices and volatility

We examine the effects of the short‐selling ban, imposed by Australian regulators in the wake of the global financial crisis, on the trading of financial stocks. Our findings argue against commonly stated reasons for imposing short‐sale bans. We find no evidence that short‐sale restrictions provide support for stock prices or that they reduce volatility. Moreover, stocks subject to the short‐selling ban suffered a severe degradation in market quality. Controlling for the adverse effects of the financial crisis on markets, we show that short‐selling restrictions increase intraday volatility, reduce trading activity and increase bid–ask spreads.     

Asymmetric effects of voluntary disclosure on stock liquidity: evidence from 8‐K filings

This paper examines whether the change in stock liquidity subsequent to voluntary disclosure is different between good news and bad news. Using voluntary 8‐K filings, we find that the increase in stock liquidity is more pronounced for firms with good news disclosure than for firms with bad news disclosure. In addition, such findings are stronger when a firm is less visible and when the short‐selling costs are high, suggesting that these two factors play an important role in increasing stock liquidity. Overall, this paper provides evidence that the tone of voluntary 8‐K news is an important determinant of stock liquidity.     

Corporate Taxes and Securitization

Most banks pay corporate income taxes, but securitization vehicles do not. Our model shows that, when a bank faces strong loan demand but limited deposit market power, this tax asymmetry creates an incentive to sell loans despite less‐efficient screening and monitoring of sold loans. Moreover, loan‐selling increases as a bank's corporate income tax rate and capital requirement rise. Our empirical tests show that U.S. commercial banks sell more of their mortgages when they operate in states that impose higher corporate income taxes. A policy implication is that tax‐induced loan‐selling will rise if banks’ required equity capital increases.     

Implications of Short Selling for Corporate Finance

Corporate managers often view short sellers as market manipulators whose actions drive their company's stock price below intrinsic value. But recent academic research suggests that some short sellers are effective in processing publicly available information and that their short selling may provide useful information to market participants. This article summarizes the authors’ own published research, which provides evidence of informed short selling by linking it to changes in corporate fundamentals. More specifically, the authors’ findings indicate that increases in short interest are reliable indicators of an economically (as well as statistically) significant decline in a company's operating performance over the following three years. And when examining changes in short interest around announcements of seasoned equity offerings, the authors also find a negative relation between an increase in short interest and future operating performance. In addition, they find that the greater the increase in short interest in the period leading up to the SEO announcement, the more negative is the stock‐price response to the announcement itself. The authors’ findings suggest that corporate managers can benefit from monitoring the short‐selling activity in their company's stock. Short‐selling data can be used to reassess corporate strategy or rethink major corporate decisions that have been announced but not carried out, and take preemptive actions to forestall impending future declines in performance and so preserve value.     

卖空机制的审计收费效应研究

卖空机制作为一种金融创新,如何在提高证券市场定价效率的同时,有效发挥外 部治理功能、改善公司治理、间接推动国内资本市场健康发展成为理论和实践中的一项重要 课题。运用多元回归模型对国内卖空机制改变审计风险、进而影响审计收费行为的实证检验表 明,随着股票卖空比率的上升,公司审计收费也相应增加。而股票卖空比率与公司审计费用受 制度环境影响显著,在市场化水平较高的地区,公司审计面临来自投资者更大的压力。此外, 公司审计收费与股票卖空比率的正相关关系会因卖空机制的存在变得更加显著。     

卖空机制能够约束内部人减持吗？——基于融资融券制度的经验证据

本文以我国放松卖空管制为视角,探究其对内部人减持的影响。研究表明,卖空机制能够抑制企业内部人减持行为。机制分析发现,卖空对内部人减持的抑制作用是通过缓解股权高溢价实现的。进一步研究表明,卖空能够抑制大股东、董事以及管理层减持,但对监事减持无影响;卖空能够降低内部人减持的获利程度,并且在内部人减持动机更大时,对内部人减持的抑制作用更强;卖空通过约束内部人减持提升了股票定价效率,还有助于降低内部人增持行为。本文的研究结论丰富了卖空和内部人减持领域的文献,并对政府部门完善制度设计具有启示意义。     

The Lead-Lag Relation Between Spot and Futures Markets Under Different Short-Selling Regimes

We examine the lead‐lag relation between index futures and the underlying index under three types of short‐selling restrictions on stocks in Hong Kong. Our results indicate that lifting short‐selling restrictions can enhance the informational efficiency of the stock market relative to the index futures. We also investigate the impact of two market characteristics, market conditions and the magnitude of mispricing on the lead‐lag relations under different short‐selling regimes. Our findings suggest that if we remove restrictions, the contemporaneous price relation between the futures and cash markets becomes stronger particularly in the falling market and when the cash market is relatively overpriced.     

卖空限制与收益可预测性——A股融资融券制度的证据

基于A股市场融资和融券余额的巨大差距,本文拓展了Hong et al.(2016)的理论模型,在融券端和融资端分别找到了影响股票收益率的变量:融券比率(融券余额/流通市值)和融资回补天数(融资比率/日均换手率)。进一步,本文利用组合价差法和Fama-MacBeth横截面回归法,实证检验了A股市场中融券比率与融资回补天数解释和预测股票收益率的能力。实证结果表明,在存在融券限制条件下,融券比率相比融券回补天数(融券比率/日均换手率)能更好地代表套利者对股票价格高估程度的看法,根据融券比率构建的等权重多空组合能带来月均1.58%的显著收益;而由于融资约束相对较少,融资回补天数相比融资比率(融资余额/流通市值)能更好地代表套利者对股票价格低估程度的看法,根据融资回补天数构建的等权重多空组合能带来月均1.28%的显著收益。实证结果与本文存在融券数量限制下的理论模型相符,且该收益率不能被多因子模型和常规股票特征所解释。     

THE ECONOMIC SIGNIFICANCE OF CONDITIONING INFORMATION ON PORTFOLIO EFFICIENCY IN THE PRESENCE OF COSTLY SHORT‐SELLING

The economic significance of conditioning information in the presence of costly short‐selling is investigated. Using a compact testing framework, results demonstrate that fixed‐weight stock‐bond portfolios appear inefficient with respect to stock‐bond portfolios with weights determined by extant predictors. However, this result is highly dependent on ex ante knowledge of the predictor set and the ability to short‐sell at low cost. In the absence of such conditions, fixed‐weight stock‐bond portfolios appear efficient with respect to conditioning information.     

卖空限制与收益可预测性——A股融资融券制度的证据

基于A股市场融资和融券余额的巨大差距,本文拓展了Hong et al.(2016)的理论模型,在融券端和融资端分别找到了影响股票收益率的变量:融券比率(融券余额/流通市值)和融资回补天数(融资比率/日均换手率)。进一步,本文利用组合价差法和Fama-MacBeth横截面回归法,实证检验了A股市场中融券比率与融资回补天数解释和预测股票收益率的能力。实证结果表明,在存在融券限制条件下,融券比率相比融券回补天数(融券比率/日均换手率)能更好地代表套利者对股票价格高估程度的看法,根据融券比率构建的等权重多空组合能带来月均1.58%的显著收益;而由于融资约束相对较少,融资回补天数相比融资比率(融资余额/流通市值)能更好地代表套利者对股票价格低估程度的看法,根据融资回补天数构建的等权重多空组合能带来月均1.28%的显著收益。实证结果与本文存在融券数量限制下的理论模型相符,且该收益率不能被多因子模型和常规股票特征所解释。     

Bank Leverage and Monetary Policy's Risk‐Taking Channel: Evidence from the United States

We present evidence of a risk‐taking channel of monetary policy for the U.S. banking system. We use confidential data on banks’ internal ratings on loans to businesses over the period 1997 to 2011 from the Federal Reserve's Survey of Terms of Business Lending. We find that ex ante risk‐taking by banks (measured by the risk rating of new loans) is negatively associated with increases in short‐term interest rates. This relationship is more pronounced in regions that are less in sync with the nationwide business cycle, and less pronounced for banks with relatively low capital or during periods of financial distress.     

The determinants of short selling: evidence from the Hong Kong equity market

While most financial regulators agree that short sellers have an important role to play in ensuring an efficiently functioning market, it is interesting to note that many did not hesitate to ban short selling during the recent financial crisis. This apparent contradiction most likely stems from a lack of understanding about what motivates short trading. In this paper, we focus on the determinants of short selling during ‘normal’ trading in the Hong Kong stock market. We find that dividend payments, company fundamentals, risk, option trading, the interest rate spread and past returns and short selling are all significant determinants of short selling.     

Short-selling,margin-trading,and stock liquidity: Evidence from the Chinese stock markets

This paper examines the impacts of two forms of leveraged trading—margin trading and short selling—on the trading liquidity of individual stocks in China. We find that trading liquidity for relevant stocks generally improves after restrictions on leveraged trading are removed. However, margin trading and short selling have opposite impacts on liquidity. During ordinary periods, margin trading benefits liquidity, whereas short selling damages liquidity; however, during market downturns, their roles are reversed. We also provide evidence suggesting that short sellers are informed traders in China and that short selling reduces stock liquidity because of the increased risk of adverse selection faced by uninformed traders.     

Are Short Sellers Informed? Evidence from the 2007–2008 Subprime Mortgage Crisis

This paper examines the short selling activities around financial firms’ announcements of asset write‐downs during the 2007–2008 subprime mortgage crisis. We find that short sellers accumulate short positions prior to write‐down announcements, and that stocks experience significantly negative returns around such announcements. These results suggest that the return predictability of short interests is due to short sellers’ informational advantage. Furthermore, we show that short sellers increase their positions significantly in the announcement month and keep increasing their positions afterward, suggesting the feedback effect of the disclosed write‐downs on financial firms’ existing exposures. The valuable information contained in the short interest should encourage regulators to mandate stock exchanges disclose short selling activities more frequently.     

Capitalizing on Catastrophe: Short Selling Insurance Stocks Around Hurricanes Katrina and Rita

We develop several hypotheses regarding short‐selling activity around Hurricanes Katrina and Rita. We find that abnormal short selling does not increase until 2 trading days after the landfall of Katrina and that short‐selling activity is much more significant around Rita. We find a substantial increase in short‐selling activity in the trading days prior to the landfall of Rita and relatively less short‐selling activity in the trading days after landfall. There is little evidence that suggests that traders short insurance stocks with more potential exposure in the Gulf region than other insurance stocks in the days before landfall.     

A Note on International Portfolio Diversification with Short Selling

In this paper, the diversification benefits of using stock index futures are examined. Empirical evidence shows that traditional diversification in international equity markets does not produce a risk adjusted performance superior to the US market. An explanation for this result is that restrictions on short selling prohibit the best allocation of resources when overseas stock markets are riskier and have worse returns. However, when such restrictions are eased for short selling in index futures markets, investors are enabled to both allocate their investments more efficiently and to construct a superior portfolio.