Who is Spanish of Origin?

A Spanish of origin according to the civil code is:

1. They are Spanish of origin:
a) Those born to a Spanish father or mother.

b) Those born in Spain to foreign parents if at least one of them had also been born in Spain. The children of diplomatic or consular officials accredited in Spain are excepted.

c) Those born in Spain to foreign parents, if both lack nationality or if the legislation of neither of them attributes a nationality to the child.

d) Those born in Spain whose affiliation is not determined. For these purposes, minors whose first known place of stay is Spanish territory are presumed born in Spanish territory.

2. Affiliation or birth in Spain, the determination of which occurs after the age of eighteen, is not in itself a cause for the acquisition of Spanish nationality. The interested party then has the right to opt for Spanish nationality of origin within a period of two years from that determination.

This means that the place of birth does not matter, as long as you are born to a Spanish father or mother. A clear example of a Spanish origin who was not born in Spain is King Juan Carlos I, who was born in Rome, Italy in 1938.

Doubts in the comments.