§ 7 DSG NRW
Collection of personal data from third persons and non-public bodies
(1)Where personal data are collected from a third person or a non-public body, the collecting party shall, upon request, inform such party about the purpose of the collection, provided that the legitimate interests of the data subject are not impaired thereby. Where the data are collected on the basis of a legal provision obligating the party to provide information, the third person or non-public body shall be informed of this provision; otherwise, the party shall be informed of the voluntary nature of the information provided.