Price Discovery in the U.S. Stock Options Market YUSIF E. SIMAAN AND LIUREN WU YUSIF E. SIMAAN In the U.S., several exchanges with different market the Securities and Exchange Commission is an associate professor of microstructure designs compete to provide quotes and (SEC) approved a plan to electronically link finance in the Graduate attract order flow on a common set of stock options. the various market centers (the “Linkage School of Business at Fordham University in In this article, we analyze how the different Plan”). The SEC has also adopted more strin- New York, NY. microstructure designs affect the price discovery of gent quoting and disclosure rules on the options
[email protected] options quotes and how they alter the flow of options market. The “firm quote” rule was applied to trading activities over time. We find that the fully the options markets on April 1, 2001. LIUREN WU electronic exchange system at the International Secu- At the time of our study, five options is an associate professor of rities Exchange (ISE), where several market makers exchanges compete to provide quotes and economics and finance in the Zicklin School of provide quotes independently and anonymously to attract order flows on a common set of stock Business, Baruch College at compete for order flow within the exchange, generates options: the American Stock Exchange the City University of New options quotes that are the most informative and the (AMEX), the Chicago Board of Options York in New York, NY. most executable, with the narrowest bid–ask spreads. Exchange (CBOE), the International Securi-
[email protected] Over time, the ISE’s leading quote quality has ties Exchange (ISE), the Pacific Stock attracted order flow to the exchange, and has com- Exchange (PCX), and the Philadelphia Stock pelled other exchanges to pursue technology Exchange (PHLX).