Abstract: A system and method for processing a multiple data controller workflow fully honors data subject opt-outs but nevertheless takes advantage of the synergy of the combined data from multiple controllers to improve the effectiveness of messaging. A data services provider performs data resolution processing against the data from each data controller. Using the results of the resolution processing, opt-out lists that are in different formats and that may track different sorts of data may all be used for the joint campaign. Metadata is added to the data so that the source data controller is tracked through the processing. The data is then combined, resulting in a master opt-out list. If a data subject has opted out with respect to any controller, then the opt-out is applied to the joint campaign.