The paper deals with the evolution of Russian unmarked indefi nite pronouns, also known as bare interrogatives, since the 18ᵗʰ century. The Russian National Corpus data suggest that the distribution of unmarked indefinites both in modern Russian and in the Russian language of the 18ᵗʰ–19ᵗʰ centuries is not in line with previous proposals. Surprisingly, unmarked indefinites are more frequent in some specific contexts compared to non-specific contexts such as imperatives or subjunctive clauses. I argue that the distribution of Russian unmarked indefi nites can be accounted for by some sort of economy principle: due to the lack of a marker of indefiniteness, unmarked indefinites tend to be used in contexts that are strongly biased toward a certain interpretation of an indefinite in terms of specificity (specific known vs. specific unknown vs. non-specific). This analysis, as I suggest, correctly predicts two typological tendencies reported on unmarked indefinites in the literature.