In the case of theses by published works (i.e. ones made up of previously published articles), be sure to take into account the journals' publishing policies in terms of open access, which are basically summarized as follows:
Articles published in journals with Creative Commons licences: your thesis can be open access
Articles you have reserved the exploitation rights for: your thesis can be open access
Articles copyrighted by the publisher: contact the publisher and ask for "permission to disseminate the thesis in the institutional repository".
In this case, the publisher may require a period of embargo before making it open access. You must include the following information in the thesis application:
Embargo up to 12 months: indicate this in the file upload form for defence of the thesis
Embargo for more than 12 months: apart from indicating it, you must provide proof of the embargo, e.g. the email sent by the publisher.
If you have a problem (e.g. with the embargo periods) or your thesis processes sensitive data that should not be made public, etc., contact the Doctoral School's Permanent Commission, which will rule on each case.