Law 39/2015:
Article 28. Documents provided by those interested in the administrative procedure .
“2. Interested parties are not obliged to provide documents prepared by any Administration, regardless of whether the presentation of the aforementioned documents is mandatory or optional in the procedure in question, provided that the interested party has expressed their consent to be consulted or request. It is presumed that the consultation or obtaining is authorized by the interested parties unless the procedure expressly states their opposition or that the applicable special law requires express consent.
3. The administrations shall not require interested parties to submit original documents, unless, exceptionally, the applicable regulations provide otherwise. Likewise, public administrations do not require interested parties to provide data or documents not required by the applicable regulations or which have previously been provided by the interested party to any Administration.
To this end, the interested party must indicate at what time and before which administrative body he submitted the aforementioned documents, and public administrations must request them electronically through their corporate networks or by consulting the data intermediation platforms or other electronic systems enabled for this purpose. It is presumed that such consultation is authorized by the interested parties unless the procedure expressly states their opposition or that the applicable special law requires express consent; in both cases, they must be informed in advance of their rights regarding the protection of personal data. Exceptionally, if the public administrations cannot obtain the aforementioned documents, they may ask the interested party to provide them again. ”