Preferred embodiments of the subject invention overcome the limitations of known trading interest dissemination and execution systems by (1) enabling market participants to limit dissemination of trading interests to only those other market participants likely to have a significant contra-interest, (2) enabling market participants to ensure that other market participants' disseminated trading interests are legitimate, and (3) enabling auctions among trading interests targeted and validated in this manner. Software of a preferred embodiment identifies likely contra-interests by analyzing information from various sources regarding certified trading interests.