Sovereign immunity — Foreign States and State-owned corporations and their property — Italian State Railways — Action for breach of loan agreement — Whether Italian State Railways entitled to jurisdictional immunity — Whether Italian State Railways endowed with independent legal personality — Acts iure imperii and iure gestionis — Requirement of close connection between case and forum — Attachment of shares — Immunity from attachment — Shares in Eurofima purchased by Italian State Railways — Legal states of Eurofima — Whether such shares immune from attachment as assets allocated for the performance of a State function — Relevance of distinction between patrimonial and administrative State assets — Whether purpose for which assets are allocated is decisive — The law of Switzerland