In discourse processing, speakers collaborate toward a shared mental model by introducing discourse referents and picking them up with the adequate linguistic forms. Discourse referents compete with each other with respect to their prominence and their accessibility for pronouns. This study focuses on transitive sentences with proper names as subjects and indefinite noun phrases as second arguments, typically direct objects. An ambiguous pronoun in the subsequent sentence may access either referent of the first sentence. Various factors have been shown to influence pronoun resolution, including informativity (how informative is the phrase in which the referent is introduced? E.g., the waiter vs. the waiter at the entrance) and information status (is the referent given or new in the context?). While both factors have been independently shown to increase referent accessibility, our visual-world eye-tracking experiment shows an original and quite unexpected effect: informativity and information status interact when it comes to the accessibility of indefinite noun phrases: a higher degree of informativity increases accessibility when a referent is brand-new, but surprisingly decreases accessibility when a referent is inferred. We discuss a potential explanation for this surprising pattern in terms of a mismatch between the denotational type of the indefinite and the type required by the modification. We conclude that indefinites strongly interact with additional semantic, contextual and communicative parameters in establishing their referents.