The complainant should not be required to contact the party under investigation before lodging a complaint in order for that complaint to be admissible. Where the complaint relates to the exercise of a right of the data subject that relies on the data subject concerned making a request to the controller, that request should be made to the controller before the lodging of the complaint.
Text as published in the Official Journal, reproduced verbatim (including any typographical quirks of the source). For the authentic version, see EUR-Lex.