[eng] This paper aims to explain, from a theoretical point of view, the behaviour of
past participle agreement with the object in situ (PPAOIS) in Majorcan Catalan. It is possible in perfect telic dynamic events, but not in Kimian and Davidsonian states, nor in some atelic dynamic constructions (like those ones with NP objects bounded by a D or Q), although it is perfectly grammatical with bare plurals and with bare mass nouns. In order for PPAOIS to be possible, it is proposed that a specific functional head (Asp, that is to say: Proc[uq][uϕ]), related to so-called inner aspect, must be present in the event structure. Asp establishes a double Agree relation with the object, in order to get its quantisation and [uϕ] features valued. The possibility is also explored that the [q] feature of Asp be interpretable. If Asp is not present in the structure, the impossibility of PPAOIS follows. Moreover, PPAOIS will be only materialised if a pro object co-referent with the full NP object moves
through a LowTop position —similar to the AgrO projection proposed by Kayne (1989).