Abstract
The main goal of this paper is to provide a solution to a puzzle regarding a constraint on multiple external possession relations in Spanish prepositional double object verbs like poner ‘put.’ When both the direct object and prepositional object are body parts with different external possessors, the subject must be the possessor of the direct object body part and a dative clitic the possessor the prepositional object body part, not the other way around. Assuming that possessor movement to theta positions is what gives rise to external possession, I claim that the unacceptable interpretation is due to a locality violation that is incurred when an external possession relation is established between a subject and prepositional object body part that crosses over another external possession relation between a dative clitic and direct object body part.