This study contributes to current trends of heritage speaker bilingualism research by examining the syntax of so-called Spanish dative-experiencer predicates ("gustar"-like verbs). Building on previous findings (e.g., Silva-Corvalán 1994; Toribio and Nye 2006), it is hypothesized that Spanish heritage speakers can project an optional agentive syntax (a use deemed ungrammatical by monolingual speakers) while still having access to the obligatory dative-experiencer syntax. It is argued that the availability of this emergent optionality, coupled with influence from English, the dominant language, conspire to promote the non target-like forms documented in previous research (e.g., Toribio and Nye 2006; de Prada Pérez and Pascual y Cabo 2011). The ensuing predictions are tested with a grammaticality judgment task that examines the informants' knowledge and use of "gustar"-like verbs in passive constructions precisely because passivization of stative predicates should be precluded from a grammar that does not allow for an agentive alternation.