The Spanish institutions collaborating with SEP have the
  approval of Spain's Ministry of Education to grant official
  university degrees. All the academic departments seeking 
  to establish student exchange programs offer degrees 
  reviewed and approved by the national   agency for quality
  evaluation and accreditation ANECA. This is the highest level
  of accreditation in Spain, equivalent to the status recognition
  awarded in the U.S. A. by regional associations

TITULO OFICIAL

A "Titulo Oficial" is a degree granted by an officially accredited institution, in a major with a curriculum that has been reviewed and approved by the ANECA

TITULO PROPIO

A "titulo propio" is a degree granted by a higher education institution, with a curriculum that has not been approved by the ANECA

TITULO DE GRADO

"Grado" is the new (Bologna Process) denomination for undergraduate 4 year degrees, in Spain, previously known as "Licenciatura"