Marketo - Marketo's powerful marketing automation software helps marketers master the art & science of digital marketing to engage customers and prospects.
Clearbit - Clearbit provides Business Intelligence APIs
ActiveCampaign - Integrated email marketing, marketing automation, and small business CRM. Send beautiful newsletters, setup behavioral based automations, and benefit from sales automation.
DataXu - Marketing analytics for brands and agencies.
Pardot - Salesforce B2B marketing automation
V12 Data - V12 Data offers rich data sets with verified addresses and emails for personalized marketing campaigns.