The Agencia Nacional de Codificación de Valores (ANCV) prepares a biannual publication that contains the list of ISIN codes of active financial instruments in its database.
From 31st December 2018 only ISIN codes allocated by the ANCV (ISIN codes that start with ES) are included in this Publication.
The mentioned publication has a biannual regular recurrence: June, 30th and December, 31st.
See publications.