What are online identifiers?
The UK GDPR specifically includes the term ‘online identifiers’ within the definition of what constitutes personal data.
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Other examples of online identifiers that may be personal data include:
- MAC addresses;
- advertising IDs;
- pixel tags;
- account handles; and
- device fingerprints.
The use of these may leave traces which, when combined with unique identifiers and other information received by servers, may be used to create profiles of individuals and identify them.
When assessing if an individual is identifiable, you must consider whether online identifiers, on their own or in combination with other information that may be available to those processing the data, may be used to distinguish one user from another, possibly by the creation of profiles of the individuals to identify them.
This may be either as a named individual or simply as a unique user of electronic communications and other internet services who may be distinguished from other users.