Sign languages are sometimes claimed to lack argument marking, yet they exhibit many devices to track and disambiguate referents. In this paper, I will argue that there are devices found across sign languages that demonstrate how object marking is a prevalent property and that these devices show clear parallels to differential object marking (DOM) as described for spoken languages. This includes animacy/prominence effects on word order and verbal modification, as well as dedicated object markers used exclusively with [+human] objects. Thus, I propose that DOM phenomena need to be taken into account in any future research on sign language structure, but also that sign languages should be accounted for in typological work on DOM.