January 24, 2009
This paper addresses a number of important market microstructure issues associated with exchange traded equity options having significant research implications for studies investigating clustering on option strike prices. Price threshold levels are examined associated with exchange listing and the automatic exercise of equity options as established by the SEC and OCC to carry out their regulatory and oversight responsibilities. Significant changes are documented including motivation for such changes. Market microstructure issues potentially impact equity options research outcomes and one important issue is documenting changes over time to the strike price grid.