The Royal House has done everything they could do.
She can renounce her dynastic rights, but that is a personal decision.
The other option is that the Parliament would remove the rights, but that would require a law was passed, and probably only be done if she is judged and condemned and she does not resign voluntarily.
She cannot renounce her rights unilaterally. As in the case of an abdication, a renunciation requires an organic law to become legally valid.
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Article 57 [Succession]
(1) The Crown of Spain is hereditary for the successors of
H.M. Don Juan Carlos I of Borbon, legitimate heir of the historic dynasty. Succession to the throne will follow the regular order of primogeniture and representation, the first line always having preference over subsequent lines; within the same line, the closer grade over the more remote; in the same grade, the male over the female; and in the same sex, the elder over the younger.
(2) The hereditary Prince, from his birth or from the time he acquires the claim, will have the title of Prince of Asturias and the other titles traditionally linked to the successor to the Crown of Spain.
(3) If all the lines entitled by law become extinct, the Parliament shall provide for the succession to the crown in the manner which is best for the interests of Spain.
(4) Those persons, who having the right to succession to the throne, contract matrimony against the express prohibition by the King and the Parliament, shall be excluded, along with their descendants, from succession to the Crown.
(5) Abdications and renunciations and any doubt in fact or inlaw which may occur in the order of succession to the Crown, shall be resolved by an organic law.[/FONT]"
Please note again that the constitution of Spain says:
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Article 64 [Countersignature]
(1) The actions of the King shall be countersigned by the President of the Government and, when appropriate, by the competent ministers. The nomination and appointment of the President of the Government and the dissolution provided for in Article
93 shall be countersigned by the President of the House of Representatives.
(2) The persons who countersign the acts of the King shall be responsible for them."
Therefore, Mariano Rajoy, who countersigned the royal decree, is legally responsible for stripping Cristina of her ducal title,
even if that was a personal decision of the King (which we don't really know for sure).
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