Legitimate interest

Legitimate interest is one of the lawful bases for processing personal data under the GDPR, available where the use is reasonable, would be expected by the person, and does not override their rights. Marketing teams lean on it for work such as existing-customer messaging and basic profiling. It is not a shortcut: the expectation is that you document a balancing assessment, make objecting easy and stop when someone objects. Separate consent rules for electronic messaging still apply on top.