This paper investigates the referential status and structure of ‘pseudo-definite’ NPs occurring in postverbal position in the unmarked type of existential sentences. These NPs are pseudo-definite in the sense that they are formally definite but in fact realize presenting rather than presuming reference (Martin 1992); they introduce new entities into the discourse. In many cases, the formal definiteness of the NP can be explained in terms of an esphoric, i.e. a ‘forward’ phoric relationship between elements within the same NP (Du Bois 1980, Martin 1992). The aim of this paper is to propose a classification of the different types of pseudo-definites in terms of the distinct nominal constructions they realize. This classification aims at being more exhaustive than the ones already available in the literature (e.g. Lumsden 1988, Ward and Birner 1995). To this end, a corpus of unmarked, or cardinal, existentials containing a formally definite postverbal NP has been analyzed. The classification obtained on the basis of the analysis of this corpus was checked against an additional corpus extraction containing attributive clauses in which a formally definite NP occurs as Attribute.