The ones that do it on their own data do. The ones that must buy it from 3rd party data miners, have significant 'startup' costs. Have to admit, its not 'fully

The ones that do it on their own data do. The ones that must buy it from 3rd party data miners, have significant 'startup' costs. Have to admit, its not 'fully online' but, with their webshop and customer card registration for in shops, its all one datapool if you ask me. https://www.forbes.com/sites/kashmirhill/2012/02/16/how-target-figured-out-a-teen-girl-was-pregnant-before-her-father-did/ https://www.forbes.com/sites/kashmirhill/2012/02/16/how-targ...