What was the full maiden name of Pablo Picasso's mother?

Pablo Picasso's mother was María Picasso López.

She was born in Spain and married José Ruiz y Blasco, an art teacher and painter who specialized in birds and other game. Under Spanish naming customs, Picasso inherited Ruiz from his father and Picasso from his mother, eventually making his maternal surname the famous name by which he was known.

Her name is also rendered as María Picasso y López, because the conjunction “y” traditionally links paternal and maternal surnames in Spanish usage. The stored form, María Picasso López, is the standard English-language version and identifies the same person.

Picasso was born in Málaga in 1881, the first child of María and José. His mother reportedly supported his artistic ambitions, and Picasso later adopted “Picasso” rather than “Ruiz” as his professional surname. This is why his name can be mistaken as coming entirely from his father, when it was actually his maternal family name.