In the context and model of the Shared Clinical History (HCC) full room has to have the exercise upward of opposition, since the consent is not required for the treatment of the data (article 6.4 of the LOPD and articles 34 to 36 of the RLOPD). The law of opposition, that it is necessary to differentiate from other rights I ARCO, it can translate into a limitation of determinate accesses, which would bring a determinate treatment of the information in modular, as it has been configured like this in the model of HCC. The applicable normative frame can condition the scope and the consequences upward of opposition. The casuístic approach of the article 6.4 of the LOPD makes that it cannot give a closed list of which the "motives" that could be considered legitimate to exercise are the law of opposition, or of it are the personal circumstances that which can fit out the exercise upward. The medical criterion results determining in order to evaluate the belonging from giving course to a request of opposition on the part of a patient.