V12 Data - V12 Data offers rich data sets with verified addresses and emails for personalized marketing campaigns.
Blueshift - The SmartHub CDP: relevant, connected experiences across the omnichannel journey driven by unified, informed, and activated data
Lotame - Make your data actionable, learn about your most valuable customers, improve ROI by targeting the right audience and increase relevance across screens.
Optimizely Data Platform - The Optimizely Data Platform is a modern CMS platform that enables you to build and nurture your digital properties, your customers, and your content with agile velocity.
Google Audience Center - 3 votes and 6 comments so far on Reddit
Dotdigital - Email marketing automation