This paper examines definiteness marking in American Norwegian (AmNo), a heritage variety of Norwegian spoken in the US. The description adds another language to the much-studied variation within Scandinavian nominal phrases. It builds on established syntactic analysis of Scandinavian and investigates aspects that are (un)like Norwegian spoken in the homeland. A central finding is that the core syntax of Norwegian noun phrases is retained in AmNo, while the morphophonological spell-out is sometimes different. Indefinite determiners, for example, are obligatory in AmNo, but some speakers produce them with non-homeland-like gender agreement. One systematic change is observed: double definiteness has been partially lost. The typical AmNo modified definite phrase lacks the prenominal determiner that is obligatory for varieties in Norway. I argue that this is a syntactic change which allows the realization of D to be optional. This is a pattern not found in the other Scandinavian languages. At the same time, this innovative structure in AmNo is not like English, the dominant language of the AmNo speakers. This demonstrates heritage language change that is distinct from both the homeland language and the dominant language.