It is a well-known fact that DET-categories (DET = articles, demonstratives, quantifiers, etc.) are obligatory in most complex nominals of languages like English, German, Italian and the like. DET-obligatoriness in these languages famously contrasts with the optionality of DET-categories in complex nominals of many Slavic languages (Russian, Serbo-Croatian, Polish and the like). Such contrasts have been argued to be derivable from an NP-DP-parameter. Previous work argues that this parameter also underlies the availability of DET-extraction and the absence thereof: thus, a subset of NP-languages allows Left Branch Extraction, while DP-languages are subject to an island constraint, the Left Branch Condition. I suggest replacing the NP-DP-divide with a lexical parameter of the functional nominalizing head n. Adopting labeling theory, I argue that the pattern of obligatory/optional External Merge and (dis-)allowed Internal Merge of DET-categories is deducible in a uniform fashion from a single property of the nominal categorizer: English, German and Italian feature "weak" n, while the mentioned Slavic languages feature "strong" n. This lexical difference correlates with morphological manifestations on the nouns in these languages.