You are just talking about a seller then. Dilution by definition is quite different and would indicate an increase in the O/S which is not occurring. http://www.investopedia.com/terms/d/dilution.asp The four types of Market Makers are listed in the link below. http://www.dummies.com/how-to/content/how-the-nasdaq-works.html Being a wholesale market maker PUMA can serve both institutional clients and other Broker/Dealers so there is no real way to tell who is selling through them. Knife STEV