Recent research shows that the judged likelihood of properties of modified nouns ("baby ducks have webbed feet") is reduced relative to judgments for unmodified nouns ("ducks have webbed feet"). This modification effect has been taken as evidence both for and against the idea that combined concepts automatically inherit properties from their constituent concepts. Experiments 1 and 2 replicate this effect and demonstrate a reversed modification effect with false properties. That is, false properties are judged more likely with modification (e.g., "purple candles have teeth" is judged more likely than "candles have teeth"). These experiments also show that properties that are neither generically true nor false are unaffected by modification. Experiments 3 and 4 manipulate participants' expectation of contrast by showing modified and unmodified nouns that either match or mismatch in terms of a property and show that the judged likelihood of properties depends on the expectations of contrast set up by the manipulation. These results show that the modification effect is primarily driven by participants' understanding of the relation of subcategories to categories, rather than by the features of the concepts being combined, suggesting that the process of property attribution in combined concepts is strongly affected by pragmatic factors and is less strongly dependent on conceptual content than most theories of conceptual combination would suggest.