When the technical file is ready, the manufacturer/importer must guarantee that the product meets the requirements of specified EU directives and relevant standards. This is done by writing and signing a Declaration of Conformity.
The Declaration of Conformity is a legal document where the manufacturer of a product certifies that the product fulfils the essential requirements in the applicable directives. The document should be signed by the person responsible for the CE marking, this is usually the CEO or the product owner etc. The Declaration of Conformity should then be a part of the technical file.