We use a unique set of equities in the when-issued market to provide new tests of the law of one price in financial markets. We compare the prices of when-issued and regular-way shares of publicly-traded subsidiaries and their parents around the time the subsidiaries are fully divested. In contrast to prior analyses of when-issued trading in equity markets, we find that the when-issued shares of the subsidiary trade at a discount. Some of the pricing differences stem from measurement factors such as exchange location and bid-ask clustering that bias the observed when-issued pricing differential away from zero. The remaining difference between the when-issued and regular-way prices is due to asymmetric movements in bid and ask quotes in the two markets. We also find evidence of temporary price pressures on the date of execution of the spinoff of the subsidiary firms that bear resemblance to the pricing in the when-issued market. We interpret the evidence as consistent with the law of one price in the presence of transaction costs.

This paper examines the degree of anonymity—the extent to which a trader is recognized as informed—on alternative market structures. We find evidence that is consistent with less anonymity on the NYSE specialist system compared to the NASDAQ dealer system. Specifically, when corporate insiders trade medium-sized quantities (500–9, 999 shares inclusive), NYSE listed stocks exhibit larger changes in proportional effective spreads than NASDAQ stocks. Taken together, these findings are consistent with Barclay and Warners (1993) contention that stealth (medium-sized) trades are more likely based on private information and insider trades are more transparent on the NYSE specialist system relative to the NASDAQ dealer system. The results support the hypothesis by Benveniste, Marcus, and Wilhelm (1992) that the unique relationship between specialists and floor brokers on the NYSE leads to less anonymity.