On the Distribution of CBOE Option Trade Prices Occurring Between Consecutive Stock Trades

This paper examines the volume distribution of option trade prices that occurs when the underlying stock price remains constant. The width of these option trade price bands provides direct evidence on the law of one price and the redundancy of options assumed in many option models. We find that index option bands are narrower than equity option bands. Furthermore, for both equity and index options, puts have narrower bandwidths than calls. In general, option price bandwidth is narrow and can be explained by the minimum price movement allowed by the Chicago Board Options Exchanges (CBOE). This supports the single price law and the redundancy assumption. The existence of bid/ask quotes on the option does not materially affect the above results although it does alter the frequency of multiple option trade prices for a given underlying stock price. We note that over 53% of option trading volume occurs without bid/ask quotes on the CBOE compared to less than 15% a decade ago. Our results suggest that the effective bid/ask spread on options is probably no larger than the minimum price movements allowed by the CBOE. Furthermore, the need for the liquidity services of market makers may be declining if the decline in quoting activity stems from cross trading (i.e. trades not involving market makers).     

Option Volume and Stock Prices: Evidence on Where Informed Traders Trade

This paper investigates the informational role of transactions volume in options markets. We develop an asymmetric information model in which informed traders may trade in option or equity markets. We show conditions under which informed traders trade options, and we investigate the implications of this for the linkage between markets. Our model predicts an important informational role for the volume of particular types of option trades. We empirically test our model's hypotheses with intraday option data. Our main empirical result is that negative and positive option volumes contain information about future stock prices.     

Large option trades, market makers, and limit orders

This article focuses on the difference between market makersand limit orders in their role as suppliers of liquidity. Forboth sources of liquidity I analyze the price behavior of stocksand options around large option trades and I estimate the premiumpaid by the initiator of the large trade. My findings suggestthat limit orders for options are 'picked off' after adversechanges in the underlying stock price. Furthermore, I find thatfor these transactions there is a permanent change in quotationsin the direction of the transaction. After transactions wheremarket makers supply liquidity, quotes tend to return to theirpretrade level.     

Informed Trading in Stock and Option Markets

We investigate the contribution of option markets to price discovery, using a modification of Hasbrouck's (1995) "information share" approach. Based on five years of stock and options data for 60 firms, we estimate the option market's contribution to price discovery to be about 17% on average. Option market price discovery is related to trading volume and spreads in both markets, and stock volatility. Price discovery across option strike prices is related to leverage, trading volume, and spreads. Our results are consistent with theoretical arguments that informed investors trade in both stock and option markets, suggesting an important informational role for options.     

Day end returns—stock price manipulation

In this paper, we examine if closing prices are manipulated. Earlier research has shown that closing prices are one of the most used benchmarks against which trader performance is evaluated. If a trader takes a big net position a given day, it is likely that he wants to enhance his performance by manipulating the closing price. We build a simple regression model to test for closing price manipulation in the Finnish stock market. Robustness checks were made for the effect of: (a) size of the net position; (b) differences in returns across firms; (c) different size of net position for different firms, block trades and spread trades. The results before close, for the base case, were in line with our hypothesis. However, the robustness checks showed that block trades and spread trades explained a part, but not all, of our results. The results after close were generally weak, but tilted towards our hypothesis.     

Stock price decreases prior to executive stock option grants

This study examines abnormal stock price changes prior to executive stock option grants. Executives have the incentive and opportunity to manage the timing of their communications of inside information to the market during the period just prior to the date of their stock-option grant so as to reduce the exercise price of their options. Executives benefit from temporary stock price decreases before the grant date and by stock price increases after the grant date. Executive stock option grants create a unique opportunity for insiders to profit by manipulating the timing of information flowing to the market without engaging in insider trading. Using data on 783 stock-option grants to chief executive officers, we find a statistically significant abnormal decrease in stock prices during the 10-day period immediately preceding the grant date.     

Which trades move prices in emerging markets?: Evidence from China's stock market

This paper extends Barclay and Warner's [Barclay, M.J. and J.B. Warner (1993), ‘Stealth trading and volatility: which trades move prices?’, Journal of Financial Economics, vol. 34, pp. 281–306.] original work on stealth trading by analysing which trades move price for the emerging Chinese stock market. A large block trade/manipulation hypothesis is proposed in addition to the stealth and public information hypotheses examined by Barclay and Warner. Using high-frequency data the results show that while medium and large-size trades are associated with disproportionately large, overall, cumulative stock price changes, it is the large-size trades (in terms of the number of transactions) which have the largest effect on cumulative price increases. Thus, while there is some support for stealth trading in the Chinese market, there are other effects in operation such as large block trades/price manipulation.     

Is there price discovery in equity options?

We use tick-by-tick quote data for 39 liquid US stocks and options on them, and we focus on events when the two markets disagree about the stock price in the sense that the option-implied stock price obtained from the put-call parity relation is inconsistent with the actual stock price. Option market quotes adjust to eliminate the disagreement, while the stock market quotes behave normally, as if there were no disagreement. The disagreement events are typically precipitated by stock price movements and display signed option volume in the direction that tends to eliminate the disagreements. These results show that option price quotes do not contain economically significant information about future stock prices beyond what is already reflected in current stock prices, i.e., no economically significant price discovery occurs in the option market. We also find no option market price discovery using a much larger sample of disagreement events based on a weaker definition of a disagreement, which verifies that the findings for the primary sample are not due to unusual or unrepresentative market behavior during the put-call parity violations.     

Stock Option Schedules and Managerial Opportunism

This study investigates some of the most important avenues that mangers use to manipulate the value of stock option grants. It also compares the use of these avenues in firms that issue scheduled options and in firms that issue irregular options. We document that before the Sarbanes‐Oxley Act (SOX), cumulative abnormal returns were significantly negative in the 30‐day window before an option grant, but cumulative abnormal returns turned significantly positive after the option grant. This pattern is more pronounced for irregular options, and the evidence supports the hypothesis that opportunistic manipulation of strike prices by CEOs maximized the value of the option grants. We find the disclosure requirement of option grants included in SOX successfully curtails opportunistic behavior in firms that issue scheduled options, but has a lesser effect stopping opportunistic behavior in firms that issue irregular options. Firms granting irregular options take larger negative discretionary accruals in advance of the grant than firms that grant scheduled options, and the degree of downward earnings management increases with the size of the subsequent grant. We further show that firms are more likely to issue irregular options when they offer larger option grants, have a less independent board, receive less analyst coverage, have a new CEO, exhibit poor prior performance, have higher stock return volatility and are smaller in size.     

The Price Impacts of Open Market Repurchase Trades

Abstract:  This paper analyzes a database of 60,000+ individual repurchase trades from the Toronto Stock Exchange. The average intraday price impact of repurchase trades is negative, since, because of execution rules, 60% are seller-initiated. Prices fall less following repurchase than matched non-repurchase trades—there is an abnormal price impact. We find evidence consistent with two hypotheses: repurchases provide price support, and the market learns that the shares are undervalued. Consistent with the latter, we find that repurchasing companies have superior timing. Share prices show abnormal losses (gains) before (after) the repurchase trades. We find no significant market reaction to the mandatory public disclosure of the trade details.     

The Informational Role of Stock and Option Volume

This article analyzes the intraday interdependence of orderflows and price movements for actively traded NYSE stocks andtheir Chicago Board Options Exchange (CBOE)-traded options.Stock net trade volume (buyer-initiated volume minus seller-initiatedvolume) has strong predictive ability for stock and option quoterevisions, but option net trade volume has no incremental predictiveability. This suggests that informed investors initiate tradesin the stock market but not in the option market. On the otherhand, both stock and option quote revisions have predictiveability for each other. Thus, while information in the stockmarket is contained in both quote revisions and trades, informationin the option market is contained only in quote revisions.     

Price,trade size,and information in securities markets

This paper investigates the effect of trade size on security prices. We show that trade size introduces an adverse selection problem into security trading because, given that they wish to trade, informed traders perfer to trade larger amounts at any given price. As a result, market makers' pricing strategies must also depend on trade size, with large trades being made at less favorable prices. Our model provides one explanation for the price effect of block trades and demonstrates that both the size and the sequence of trades matter in determining the price-trade size relationship.     

Risk sharing in a financial market with endogenous option prices

This article investigates a financial market in which investors may trade in risk-free bonds, stock and put options written on the stock. In each period, stock and option prices are simultaneously determined by market clearing. While the introduction of put options will decrease the systematic risk in the financial market, it will increase the price of risk. Investors with mean-variance preferences will generally hold portfolios containing the primary asset and the put option and may use the option to increase the risk in their wealth position in exchange for higher returns. Aggregate wealth is unaffected by an option market when there are no spillover effects on stock prices, and it is shown that short selling of options will increase the volatility of individual wealth positions. Investors with erroneous beliefs may on average be better off not trading in put options.     

Market pricing of executive stock options and implied risk preferences

When managers get to trade in options received as compensation, their trading prices reveal several aspects of subjective option pricing and risk preferences. Two subjective pricing models are fitted to show that executive stock option prices incorporate a subjective discount. It depends positively on implied volatility and negatively on option moneyness. Further, risk preferences are estimated using the semiparametric model of Aït-Sahalia and Lo (2000). The results suggest that relative risk aversion is just above 1 for a certain stock price range. This level of risk aversion is low but reasonable, and it may be explained by the typical manager being wealthy and having low marginal utility. Related to risk aversion, it is found that marginal rate of substitution increases considerably in states with low stock prices.     

Option prices and stock market momentum: evidence from China

Option prices tend to be correlated to past stock market returns due to market imperfections. We unprecedentedly examine this issue on the SSE 50 ETF option in the Chinese derivatives market. To measure the price pressure in the options market, we construct an implied volatility spread based on pairs of the SSE 50 ETF option with identical expiration dates and strike prices. By regressing the implied volatility spread on past stock returns, we find that past stock returns exert a strong influence on the pricing of index options. Specifically, we find that SSE 50 ETF calls are significantly overvalued relative to SSE 50 ETF puts after stock price increases and the reverse is also true after the stock price decreases. Moreover, we validate the momentum effects in the underlying stock market to be responsible for the price pressure. These findings are both economically and statistically significant and have important implications.     

Earnings Announcements,Stock Price Adjustment,and the Existence of Option Markets

This paper employs a new approach to study the effects of option trading on the behavior of underlying stock prices. Extant research compares distributional properties of the stock price at two points in time divided by an event in the option market that might affect price behavior. As an alternative, we examine the stock price adjustment to the release of quarterly earnings using samples of firms with and without listed options. We find the two samples exhibit different adjustment processes, with the nonoption firms requiring substantially more time to adjust.     

Are corporate managers savvy about their stock price? Evidence from insider trading after earnings announcements

We find that insiders trade as if they exploit market underreaction to earnings news, buying (selling) after good (bad) earnings announcements when the price reaction to the announcement is low (high). We also find that insider trades attributable to public information about earnings and the price reaction generate abnormal returns. By demonstrating that managers spot market underreaction to earnings news, our results imply that managers are savvy about their company’s stock price.     

Finance, Politics, and the Accounting for Stock Options

The politics of option accounting crosses party lines, reflecting both the interests of the affected constituencies and the desire for power over standard setting. House Bill HR-3574, which mandates an assumption of zero stock price volatility, runs counter to the recently passed Financial Accounting Standards Board (FASB) rule requiring fair-value expensing of stock options. For any option issued at or out of the money, where strike prices are normally set, expense recognition is zero under this bill's mandated assumption.
Besides excessive use of stock options, the lack of a "final peace" in the option accounting war appears to have encouraged another questionable corporate practice. This article examines a sample of "six-and-one restructurings," exchanges of options in which expensing of re-priced (deep out-of-the-money) options can be avoided if employees wait at least six months and one day before receiving new options. The authors found that market-adjusted stock prices tend to decrease during the six-month period before the strike price is reset. This result provides one more reason why companies should be required to use fair-value option pricing models to expense options.     

Intraday Price Change and Trading Volume Relations in the Stock and Stock Option Markets

This study investigates intraday relations between price changes and trading volume of options and stocks for a sample of firms whose options traded on the CBOE during the first quarter of 1986. After purging the price change series of the effects of bid/ask spreads, multivariate time-series analysis is used to estimate the lead/lag relation between the price changes in the option and stock markets. The results indicate that price changes in the stock market lead the option market by as much as fifteen minutes. The analysis of trading volume indicates that the stock market lead may be even longer.     

Locals,foreigners, and multi-market trading of equities: Intraday evidence from Thailand

We study stock market orders and trades in a developing country, Thailand, where foreign ownership limits partially segment local and foreign investors into two distinct markets. Some foreigners forgo voting rights and distributions to trade on the “local board”, while some locals forgo such benefits and pay a price premium to trade on the “foreign board”. Regardless of nationality, these cross-market traders typically submit orders when liquidity is high, fill orders at relatively beneficial prices, exploit patterns in stock prices across markets, display profitable holding-period returns, and enhance price discovery. This suggests that skilled, informed trading that affects market quality does not depend on trader nationality.