Email Appending also known as e-appending. This service is traditionally  practiced in market to minimize the cost by approaching wrong audience and also to reduce investment on market  using email channel. By following data mining steps, data are cleansed to remove the duplicates in data and also checks for the accuracy of data, then the buyers Database are scanned against the vendor's Database, if required key fields like revenue, postal address and many other information are missing then it will appended based on clients requirement . The only contacts which has permission are merged. OnlineLeads since 2002 providing  this service to prospects which literally enabled audience to connect with their targete audience via  email campaign. http://www.onlineleadsinc.com/email-appending-services