By default Nosto's extension uses Prestashop's newsletter subscription as a source of information for populating this field. In other words, if a customer is also a newsletter subscriber marketing_permission
field will be set to true
and Nosto considers that the customer has given GDPR compliant marketing permission consent. If a customer is not a newsletter subscriber marketing_permission
field will be left empty and Nosto considers that the customer has not given GDPR compliant marketing permission.