57 could not allege an absolute lack of compliance, since partial pension payments were made between 1999 and 2001. Therefore, the State concluded that it was not responsible for the violation of Article 21 of the Convention. D.2 Considerations of the Court 212. In its case law, the Court has developed217 a broad concept of property that encompasses, inter alia, the use and enjoyment of possessions, defined in the case of Ivcher Bronstein v. Peru as “those material objects that may be appropriated, or intangible objects, as well as any right that may form part of a person’s patrimony.218 The Court has also considered that “this concept includes all movable and immovable property, corporal and incorporeal elements, and any other intangible object of any value.”219 213. In the cases of the Five Pensioners v. Peru and Acevedo Buendía et al. v. Peru, the Court declared a violation of the right to property owing to the patrimonial effects caused by the failure to comply with judgments that sought to protect the right to a pension, which had been acquired by the victims, in accordance with domestic laws. In the case of Five Pensioners,220 the Court considered that, from the time that a pensioner pays his contributions to the pension fund, ceases to work for the institution in question, and opts for the retirement regime established by law, he acquires the right to have his pension governed by the terms and conditions established by said law. In the case of Acevedo Buendía et al. v. Peru,221 the Court declared that the right to a pension acquired by a pensioner produces “patrimonial effects,” which are protected under Article 21 of the Convention. 214. The Court also emphasizes and concurs with the points made by Christian Courtis in his expert opinion, that “[t]he benefits derived from social security, including the right to an old-age pension, form part of the right to property and both must be protected against arbitrary interference by the State. The right to property may even cover the legitimate expectations of the beneficiary, particularly when he has paid contributions through a contributory system. With even greater reason, it should cover the rights acquired once the conditions are met to obtain a benefit such as the oldage pension, particularly when that right has been recognized in a judicial ruling. Furthermore, among the wide range of interests protected by the right to property, social security benefits acquire particular significance in terms of their nature as an alimentary and income-substituting benefit.”222 215. In the instant case, the Court observes that, based on Decree Law No. 20530, Mr. Muelle Flores had acquired the right to an equalized pension upon retirement, on September 30, 1990, from his position as Assistant General Manager of the State-owned company Tintaya S.A. (supra para. 43). Likewise, his inclusion in that pension scheme was declared lawful following an administrative 217 Cf. Case of “Five Pensioners” v. Peru. Merits, reparations and costs. Judgment of February 28, 2003. Series C No. 98, para. 173. Cf. Case of Acevedo Jaramillo et al. v. Peru, supra, para. 294. Cf. Case of Abrill Alosilla et al. v. Peru, supra, para. 82. 218 Cf. Case of Ivcher Bronstein v. Peru. Reparations and costs. Judgment of February 6, 2001. Series C No. 74, paras. 120-122. Cf. Case of Salvador Chiriboga v. Ecuador. Preliminary objection and Merits. Judgment of May 6, 2008. Series C No. 179, para. 55. Cf. Case of Acevedo Buendía et al. (“Discharged and Retired Employees of the Comptroller’s Office) v. Peru. Preliminary objection, merits, reparations and costs. Judgment of July 1, 2009. Series C No.198, para. 84. Cf. Case of Abrill Alosilla et al. v. Peru, supra, para. 82. 219 Cf. Case of Ivcher Bronstein v. Peru, supra, para. 122. 220 Cf. Case of “Five Pensioners” v. Peru, supra, para. 103. 221 Cf. Case of Acevedo Buendía et al. (“Discharged and Retired Employees of the Comptroller’s Office) v. Peru, supra, para. 85. 222 Cf. Affidavit rendered by Christian Courtis on August 30, 2018 (evidence file, folio 1833).