Joined Cases T-345/19, T-346/19, T-364/19 to T-366/19, T-372/19 to T-375/19, and T-385/19: Judgment of the General Court of 10 February 2021 — Santini and Others v Parliament (Institutional law — Single statute for Members of the European Parliament — Members of the European Parliament elected in Italian constituencies — Adoption by the Ufficio di Presidenza della Camera dei deputati (Office of the President of the Italian Chamber of Deputies, Italy) of Resolution No 14/2018, on pensions — Alteration of the amount of the pensions of Italian national Members of Parliament — Corresponding alteration by the European Parliament of the amount of the pensions of certain former Members of the European Parliament elected in Italy — Competence of the author of the act — Obligation to state reasons — Acquired rights — Legal certainty — Legitimate expectations — Right to property — Proportionality — Equal treatment — Non-contractual liability — Sufficiently serious breach of a rule of law conferring rights on individuals)