Abstract: A computer system is provided that includes a paired list of data transaction requests on which a matching process is performed. There are multiple different types of data transaction requests that are stored in the paired list including data transaction requests with midpoint attributes and data transaction requests with discretion attributes. The computer system may determine how the multiple different types of data transaction requests may be match against each other. Two matching processes can be used to determine if a match exists between the first and second sides of the paired list. Matches that are determined at private values are not disseminated to third-parties via public market data feeds.