What are special categories of personal data?

Article 9 of the GDPR applies even stricter restrictions to the processing of special categories of personal data, defined as: ‘personal data revealing racial or ethnic origin, political opinions, religious or philosophical beliefs, or trade-union membership, as well as the processing of genetic data, biometric data uniquely identifying a person, data concerning health or data concerning a person’s sex life or sexual orientation.’ All this data has additional processing restrictions. Biometric data is defined as ‘personal data resulting from specific technical processing relating to the physical, physiological or behavioural characteristics of a natural person which permits or confirms the unique identification of that natural person, in particular facial images or dactyloscopic data’ (Article 4(14) of the GDPR). Health data is defined as ‘personal data relating to the physical or mental health of a natural person, including the provision of health services, which reveal information about his or her state of health’ (Article 4(15) of the GDPR).