[1] Apesteguia (2004), in a paper describing a new Patagonian sauropod, Bonitasaura salgadoi, may have been the first to properly define the taxon, although without the use of cladistic analysis: the stemclade consisting of all titanosaurs more closely related to Nemegtosaurus than to Saltasaurus.

Quaesitosaurus was placed in the Saltasaurinae and Nemegtosaurus in a new, unnamed "Rapetosaurus clade" (which, under ICZN rules, would, if named, be termed subfamily Nemegtosaurinae or tribe Nemegtosaurini, depending on its position).

[10] In a paper discussing new anatomical data on the skull of Tapuiasaurus, Wilson and his colleagues cast doubt on the monophyly of Nemegtosauridae, judging from a rescoring of the Zaher et al. 2011 cladistic analysis regarding cranial characters.

[11] A 2014 cladistic analysis gleaning new anatomical data from Diamantinasaurus also rendered Nemegtosauridae paraphyletic, with Rapetosaurus falling out as a member of Saltasauridae closer to Isisaurus than to Nemegtosaurus.

Further work on the discovered postcrania was required to resolve the relationships of Nemegtosaurus and Opisthocoelicaudia, but it was preliminarily retained as a clade of saltasauroid that may end up as a synonym of Opisthocoelicaudiinae or even Lirainosaurinae.