DotCom Mania: The Rise and Fall of Internet Stock Prices

This paper explores a model based on agents with heterogenous beliefs facing short sales restrictions, and its explanation for the rise, persistence, and eventual fall of Internet stock prices. First, we document substantial short sale restrictions for Internet stocks. Second, using data on Internet holdings and block trades, we show a link between heterogeneity and price effects for Internet stocks. Third, arguing that lockup expirations are a loosening of the short sale constraint, we document average, long‐run excess returns as low as ?33 percent for Internet stocks postlockup. We link the Internet bubble burst to the unprecedented level of lockup expirations and insider selling.     

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.     

Regulatory Uncertainty and Market Liquidity: The 2008 Short Sale Ban's Impact on Equity Option Markets

We examine how the September 2008 short sale restrictions and the accompanying confusion and regulatory uncertainty impacted equity option markets. We find that the short sale ban is associated with dramatically increased bid‐ask spreads for options on banned stocks. In addition, synthetic share prices for banned stocks become significantly lower than actual share prices during the ban. We find similar results for synthetic share prices of hard‐to‐borrow stocks, suggesting that the dislocation in actual and synthetic share prices is attributable to the increased hedging costs for options on banned stocks during the short sale ban.     

Options,Short Sales,and Market Completeness

This paper presents empirical evidence that trading in options contributes to both transactional and informational efficiency of the stock market by reducing the effect of constraints on short sales. The significantly higher average level of short interest exhibited by optionable stocks supports the argument that options facilitate short selling. We also find significant effects on option prices, related to the short interest in the underlying stock. We then present evidence that options also increase information efficiency. Earlier work, that is replicated and extended here, has suggested that short sale constraints cause stock prices to underweight negative information. Options appear to reduce that effect.     

Why Option Prices Lag Stock Prices: A Trading-based Explanation

While many studies find that option prices lead stock prices, Stephan and Whaley (1990) find that stocks lead options. We find no evidence that options, even deep out-of-the-money options, lead stocks. After confirming Stephan and Whaley's results, we show their results can be explained as spurious leads induced by infrequent trading of options. We show that the stock lead disappears when the average of the bid and ask prices is used instead of transaction prices. Hence, we find no evidence of arbitrage opportunities associated with the stock lead.     

Robust pricing and hedging under trading restrictions and the emergence of local martingale models

We pursue the robust approach to pricing and hedging in which no probability measure is fixed, but call or put options with different maturities and strikes can be traded initially at their market prices. We allow the inclusion of robust modelling assumptions by specifying a set of feasible paths on which (super)hedging arguments are required to work. In a discrete-time setup with no short selling, we characterise absence of arbitrage and show that if call options are traded, then the usual pricing–hedging duality is preserved. In contrast, if only put options are traded, a duality gap may appear. Embedding the results into a continuous-time framework, we show that the duality gap may be interpreted as a financial bubble and link it to strict local martingales. This provides an intrinsic justification of strict local martingales as models for financial bubbles arising from a combination of trading restrictions and current market prices.     

Risk-taking incentives of executive stock options and the asset substitution problem

Various theoretical models show that managerial compensation schemes can reduce the distortionary effects of financial leverage. There is mixed evidence as to whether highly levered firms offer less stock‐based compensation, a common prediction of such models. Both the theoretical and empirical research, however, have overlooked the leverage provided by executive stock options. In principle, adjusting the exercise prices of executive stock options can mitigate the risk incentive effects of financial leverage. We show that the near‐universal practice of setting option exercise prices near the prevailing stock price at the date of grant effectively undoes most of the effects of financial leverage. In a large cross‐sectional sample of Canadian option‐granting firms, we find evidence that executives' incentives to take equity risk are negatively rather than positively related to the leverage of their employers.     

Changing the rules again: Short selling in connection with public equity offers

We study the impact of two recent regulations that impose restrictions on short selling. First, since October 2007 any investor that short sells a firm’s stock is prohibited from purchasing shares in the firm’s seasoned equity offering (SEO) if the short occurred in the five days prior to the offering (pursuant to an amendment to Rule 105). Previously Rule 105 only disallowed investors from covering a pre-issue short sale with shares purchased in the offering. We hypothesize that the amended rule has the unintended consequence of greater discounting for overnight offers, which are not announced in advance, because the rule excludes some potential buyers and thereby forces underwriters to set lower offer prices to fully distribute the offer. The evidence supports this hypothesis. Second, we examine the impact of the SEC’s 2008 Emergency Order that greatly curtails naked short selling on all stocks under its jurisdiction. We find that the Emergency Order is associated with large increases in discounting for offers announced in advance, suggesting that the removal of naked short sellers is associated with reduced pre-SEO pricing efficiency. Taken together, the results imply that recent restrictions on short selling have significant unintended effects on the capital raising process.     

STOCK PRICES AND INFLATION

Numerous empirical studies establish that inflation has a negative short‐run effect on stock returns but few studies report a positive, long‐run Fisher effect for stock returns. Using stock price and goods price data from six industrial countries, we show that long‐run Fisher elasticities of stock prices with respect to goods prices exceed unity and range from 1.04 to 1.65, which tends to support the Fisher effect. We also find that the time path of the response of stock prices to a shock in goods prices exhibits an initial negative response, which turns positive over longer horizons. These results help reconcile previous short‐run and long‐run empirical evidence on stock returns and inflation. Also, they reveal that stock prices have a long memory with respect to inflation shocks, such that investors should expect stocks to be a good inflation hedge over a long holding period. JEL Classification: G12     

A Long‐Run Performance Perspective on the Technology Bubble

The events surrounding the stock price peak of March 2000 are commonly interpreted as the bursting of a technology or Internet bubble, with some researchers pointing out that the pattern could also arise in fundamental models. We inform the debate by studying the long‐run performance of Internet and technology stocks from March 2000 onward. Using calendar‐time regressions, we do not find conclusive evidence of negative abnormal returns. The results are consistent with a new interpretation of the events; namely, the price drop of the early 2000s was not warranted in light of future cash flows and risk.     

Distribution of Ownership,Short Sale Constraints,and Market Efficiency: Evidence from Cross‐Listed Stocks

We investigate the interplay between the distribution of ownership, short sale constraints, and market efficiency. Using minute‐by‐minute data during the period surrounding the short sale ban of 2008, we demonstrate that short sale restrictions cause price disparities among cross‐listed stocks when ownership in the stocks is distributed unevenly across the two markets. The stocks tend to trade at a premium in the market where long sellers are relatively scarcer, which reduces the speed at which prices adjust to bad news. The premium is driven primarily by an increase on the ask side of the market where ownership is thinner, is only evident when prices are moving down, and disappears quickly.     

Options trading volume and stock price response to earnings announcements

We examine the effect of options trading volume on the stock price response to earnings announcements over the period 1996–2007. Contrary to previous studies, we find no significant difference in the immediate stock price response to earnings information announcements in samples split between firms with listed options and firms without listed options. However, within the sample of firms with listed options stratified by options volume, we find that higher options trading volume reduces the immediate stock price response to earnings announcements. This conforms with evidence that stock prices of high options trading volume firms have anticipated and pre-empted some earnings information in the pre-announcement period. We also find that higher abnormal options trading volume around earnings announcements hastens the stock price adjustment to earnings news and reduces post-earnings announcement drift.     

Role of Speculative Short Sales in Price Formation: The Case of the Weekend Effect

We argue that short sellers affect prices in a significant and systematic manner. In particular, we contend that speculative short sales contribute to the weekend effect: The inability to trade over the weekend is likely to cause these short sellers to close their speculative positions on Fridays and reestablish new short positions on Mondays causing stock prices to rise on Fridays and fall on Mondays. We find evidence in support of this hypothesis based on a comparison of high short-interest stocks and low short-interest stocks, stocks with and without actively traded options, IPOs, zero short-interest stocks, and highly volatile stocks.     

Efficiency and the Bear: Short Sales and Markets Around the World

We analyze cross‐sectional and time‐series information from 46 equity markets around the world to consider whether short sales restrictions affect the efficiency of the market and the distributional characteristics of returns to individual stocks and market indices. We find some evidence that prices incorporate negative information faster in countries where short sales are allowed and practiced. A common conjecture by regulators is that short sales restrictions can reduce the relative severity of a market panic. We find strong evidence that in markets where short selling is either prohibited or not practiced, market returns display significantly less negative skewness.     

Family‐Controlled Firms and Informed Trading: Evidence from Short Sales

We investigate the relation between organization structure and the information content of short sales, focusing on founder‐ and heir‐controlled firms. Our analysis indicates that family‐controlled firms experience substantially higher abnormal short sales prior to negative earnings shocks than nonfamily firms. Supplementary testing indicates that family control characteristics intensify informed short selling. Further analysis suggests that daily short‐sale interest in family firms contains useful information in forecasting stock returns; however, we find no discernable effect for nonfamily firms. This analysis provides compelling evidence that informed trading via short sales occurs more readily in family firms than in nonfamily firms.     

Can Short Restrictions Actually Increase Informed Short Selling?

We use the 2008 short selling regulations to test whether short sale restrictions can increase informed short selling. For the preborrow requirement, we find more negative price reactions to short interest announcements though no reliable increase in the price impact of short sales volume. For the stocks with banned short sales, we find an increase in the price impact of short sale volume though no reliable change in the price reaction to short interest announcements. Both restrictions, however, are associated with increased informed trading. Our results suggest that short restrictions will not reduce informed short selling and may actually result in an increase by increasing the proportion of informed short sellers..     

Comparing the information in short sales and put options

Prior work shows that both short sales and put options contain information about future stock prices. In this study, we compare the return predictability in short sales to the return predictability in put options. The motivation for this comparison is based on the theoretical argument that informed traders can choose between short sales and put options when establishing short positions in a particular stocks. Results in this paper suggest that the underperformance of stocks with high short-selling activity is approximately four times larger than the underperformance of stocks with high put-option activity. While stocks that are most likely to face binding short-sale constraints drive the underperformance caused by put-option activity, we still find that short sales are generally more informative about future prices.     

Short sale constraints,heterogeneous interpretations,and asymmetric price reactions to earnings announcements

This study tests Miller’s (1977) overpricing hypothesis from a new angle. Specifically, we investigate the effects of heterogeneous interpretations on price reactions to earnings announcements. We find that the difference between good news and bad news earnings response coefficients increases with the degree of heterogeneous interpretations in the presence of short sale constraints. This pattern is more pronounced when short sale constraints are more binding. These findings support the notion that, under short sale constraints, stock prices selectively incorporate more optimistic opinions rather than the average opinion of all investors. Therefore, reducing short sale constraints should facilitate price discovery and improve price efficiency. This study complements recent studies examining the joint effect of short sale constraints and ex ante opinion divergence on price reactions to earnings announcements.     

Executive Compensation and the Maturity Structure of Corporate Debt

Executive compensation influences managerial risk preferences through executives' portfolio sensitivities to changes in stock prices (delta) and stock return volatility (vega). Large deltas discourage managerial risk‐taking, while large vegas encourage risk‐taking. Theory suggests that short‐maturity debt mitigates agency costs of debt by constraining managerial risk preferences. We posit and find evidence of a negative (positive) relation between CEO portfolio deltas (vegas) and short‐maturity debt. We also find that short‐maturity debt mitigates the influence of vega‐ and delta‐related incentives on bond yields. Overall, our empirical evidence shows that short‐term debt mitigates agency costs of debt arising from compensation risk.     

Short‐Selling Bans Around the World: Evidence from the 2007–09 Crisis

Most regulators around the world reacted to the 2007–09 crisis by imposing bans on short selling. These were imposed and lifted at different dates in different countries, often targeted different sets of stocks, and featured varying degrees of stringency. We exploit this variation in short‐sales regimes to identify their effects on liquidity, price discovery, and stock prices. Using panel and matching techniques, we find that bans (i) were detrimental for liquidity, especially for stocks with small capitalization and no listed options; (ii) slowed price discovery, especially in bear markets, and (iii) failed to support prices, except possibly for U.S. financial stocks.