 Jacques Gauthier, in 1986, found that Deinocheiridae was synonymous with Ornithomimidae.He used Ornithomimidae as a similar group to Ornithomimosauria, including "Elaphrosaurus" (a non-coelurosaurian), "Ajancingenia" (then "Ingenia"; an oviraptorid), "Ornithomimus", "Struthiomimus", "Archaeornithomimus", "Gallimimus", "Dromiceiomimus", "Garudimimus" and "Deinocheirus".In a 2014 study by Yuong-Nam Lee and his colleagues, describing new specimens of "Deinocheirus", it was found that the genus was indeed a close relative of "Ornithomimus", and that the family Deinocheiridae was valid and not monotypic.