What is the nature of legal reality? This essay analyses the answer to this ontological question framed by the Portuguese legal philosopher Luis Cabral de Moncada (1888-1974). For Moncada, legal reality has essentially a semantic nature, since meaning is an essential component of legal reality. According to Moncada, legal reality comprises a pre-legal substratum and a legal meaning. In particular, legal realities are realities referring to certain values which assign them a particular meaning. This idea of the semantic nature of law is also present in three other theories of law: (i) Emil Lask's philosophy of law(1905), (ii) Czeslaw Znamierowski's social ontology (1924) and (iii) Hans Kelsen's pure theory of law (1934)