1. A method for checking a value document of a specified value document type for a presence of at least one irregularity of at least one specified type, in which an ultrasound data record is captured, which describes in locally resolved fashion at least one ultrasound property, of the value document; a deviation data record is ascertained, which describes in locally resolved fashion a deviation between an ultrasound data record and a model and is ascertained such that the deviation described thereby is minimal with respect to the model, wherein the model comprises a model for location dependence of the at least one ultrasound property of reference value documents of the specified value document type without irregularities of the at least one specified type, wherein the model defines a plurality of model data records differing from each other, which describe the at least one ultrasound property in location-dependent fashion; and using the deviation data record, checking whether an indication of an irregularity of the at least one specified type is present on the value document.