This paper examines the extent to which second language (L2) speakers of French acquire the semantic and pragmatic (or interpretive) properties associated with the c'est-cleft, specifically the exhaustive inference. This phenomenon is relevant to theories of language acquisition because it is situated at the interface of syntax and pragmatics. The results from a forced-choice task challenge the empirical adequacy of the interface hypothesis (Sorace, 2011, 2012; Sorace & Filiaci, 2006), which claims that external interfaces between a linguistic module and a cognitive module remain problematic even at the highest levels of L2 acquisition. The results from 40 L2 learners at three proficiency levels reveal development from nontargetlike to nativelike behavior. In particular, the high-proficiency group interprets the c'est-cleft, as well as canonical subject–verb–object sentences and sentences with exclusives (i.e., seul(ement) “only”), in a statistically identical way to the French native speaker control group.