What is the difference between a Data Controller and Data Processor under GDPR and how does this impact Performance Marketing?

What is the difference between a Data Controller and Data Processor under GDPR and how does this impact Performance Marketing?

A data controller determines the purpose and means of processing personal data, whereas a data processor is responsible for processing data on behalf of the controller. For performance marketing campaigns this means that REaD Group is the Data Controller when the campaign is broadcast and the client becomes a data controller when an individual registers on the client’s landing page. The data processor would be the email service provider which is processing the campaign on behalf of REaD Group.