Caja de Ahorros Municipal de Vigo-Caixavigo (the plaintiff) commenced proceedings against Pesquera Rampa SA (the defendant) to enforce a ship mortgage over the MV Rampa, flagged in Spain. Sociedad de Seguros Mutuos Marítimos de Vigo, an insurance company, appeared in the process as a third-party intervener claiming the payment of the ship's insurance premiums for the past two years. The insurance company alleged that it had a privileged credit according to the local law. The plaintiff argued that the local legal provisions invoked by the insurance company were superseded by the Maritime Liens and Mortgage Convention 1926 (the MLM Convention 1926), ratified by Spain on 2 June 1930, which does not grant the preference of maritime privilege to the credit claimed by the insurance company.

The first instance Court dismissed the insurer's claim, and the decision was affirmed by the Court of Appeal. The insurance company recurred this decision in cassation before the Tribunal Supremo/Supreme Court (SC).

Held: The SC affirmed the decision. The SC stated that the issue in this case was to determine the scope of application of the MLM Convention 1926 and whether it applied to this case even though all the parties involved were Spanish nationals. The MLM Convention 1926 had been substituted by the MLM Convention 1967. However, according to art 25 of the latter Convention, as Spain has not ratified nor adhered to this Convention, the MLM Convention 1926 remains in force and applicable in Spain. This Convention, explained the SC, has the purpose of granting the character of privileged credits of general applicability to those claims established in art 2, preventing the national laws of granting such character to credits other than those listed in that provision, as stated in art 3. The credit of the insurance company is not included in the list. That principle prevents any deviation to attend the nationality of the parties exclusively. The rights established in the Convention can only be altered by making the efficacy of the privilege conditional on formalities that the internal law may require, but not because of the nationality of the parties. The prerequisite for the application of the MLM Convention 1926 is that the ship is registered in a member State, and Spain is such a State. The MLM Convention 1926 represents a general and prevailing legal instrument, whatever the nationality of the privileged credits attaching the mortgaged ship is, with direct and integrative application in Spain, via legislation that is part of its internal legal order. Therefore, it has preference over the privileges established in the local law, provisions that lost effect by the introduction of the norms contained in the Convention. The Convention applies with general effects if the affected ship is flagged in Spain, regardless of the nationality of the parties involved. Otherwise, there would be normative duplicity that may produce, in intentional cases, a real abuse of rights. If the Convention had pursued to make an exception of the prevalence of the national law, this would have been expressly stated, as it is in section II of the Protocol of Signature regarding national laws conferring a lien upon public insurance associations.