This paper proposes a new analysis of non-subject relative constructions involving a participial base modifying a head and a participant originally encoded as a possessor. A diachronic analysis explains how these possessive constructions in attributive function serve as a source for TAM values characteristic for verb forms that emerge in this relative function. The reconstructed pathway of change thus represents an original case of verbal morphology grammaticalizing out of syntactic and discursive functions marked within the noun phrase.