Embodiments of the present invention generally provide a system, method and article of manufacture for validating annotations describing one or more portions of a data object. In general, prior to displaying a requested annotation, a current change detection value may be calculated from current data extracted from portions of the data object described by the annotation. The current change detection value may be compared to a previously saved change detection value calculated from data extracted from the portions of the data object at the time the annotation was generated. A mismatch in the current change detection value and the previously saved change detection value indicates a change in the annotated portions of the data object, which may render the annotation invalid. The annotated portions of the data object may be continuous or discontinuous.