security investigation
as defined in Commission Decision (EU, Euratom) 2015/444 of 13 March 2015 on the security…, Article 9, point (5) (Definitions)
the investigative procedures conducted by the competent authority of a Member State in accordance with its national laws and regulations in order to obtain an assurance that nothing adverse is known which would prevent an individual from being granted a security clearance up to a specified level (CONFIDENTIEL UE/EU CONFIDENTIAL or above).