According to Ranko Matasovic in the introduction to his 2009 Etymological Dictionary of Proto-Celtic : "Celtiberian...is almost certainly an independent branch on the Celtic genealogical tree, one that became separated from the others very early.

Compare Umbrian ferest "he/she/it shall make" or Ancient Greek δείξῃ deiksēi (aorist subj.)

It is generally fronted to -n in Gaulish (exceptional cases, for instance on the Larzac tablet, are probably due to influence from Latin): boustom "stable.

[23] The Indo-European third person verbal ending system seems to be evident, though the exact meaning of many verbs remains unclear: primary singular active *-ti in ambitise-ti (Botorrita I, A.5), '(that someone) builds around > encloses' from *h₂m̥bhi-dʰingʰ-s-e-ti, and auzeti, secondary *-t > /θ/ written in terbere-z (SP.02.08, B-4) and perhaps kombalke-z; primary plural active *-nti in ara-nti (Z.09.24, A-4) and zizonti "they sow" (or perhaps "they give" with assimilation of the initial do the medial ),[24] secondary *-nt perhaps in atibio-n (Z.09.24, A-5), middle voice *-nto in auzanto (Z.09.03, 01) and perhaps esianto (SP.02.08 A-2).

[25] A third person imperative *-tо̄d > -tuz perhaps is seen in da-tuz "he must give" (Bronze plaque of Torrijo del Campo), usabituz, bize-tuz (Botorrita I A.5) and dinbituz 'he must build' < *dʰingʰ-bī-tōd.

[32] Another archaic Indo-European feature is the use of the relative pronoun jos and the repetition of enclitised conjunctions such as kwe.

[35] A bronze plaque found in Torrijo del Campo, Teruel province in 1996, using the eastern Celtiberian script.