This paper examines the syntax of partitive constructions with superlatives in French and the realization of gender in constructions with an animate noun, and focuses on contexts that allow gender mismatches (la plus intelligente de mes gentils professeurs ‘the most intelligent of my kind professors'). We show that such mismatches are allowed in French superlative partitives that contain a default masculine noun. To account for the mismatches, we propose that the nouns involved have an unvalued gender feature that can be assigned a sex specification in the course of the derivation. For superlative partitives we propose that this specification takes place in a Gender Phrase in the outer DP. Furthermore, we show that quantified partitives (e.g. three of the books) behave differently from superlative partitives, a fact we try to explain in terms of structural differences. We distinguish between partitives with an of-complement and non-canonical partitives with an ‘among'-PP or a preposed ‘of'-phrase. We also claim that our data can provide further insight into the role of locality in semantic agreement: we compare superlative partitives to quantified partitives in terms of agreement, and suggest that the two types of partitives should be placed in different positions on an Agreement Hierarchy.