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The new Ge‐based skutterudites MPt4Ge12 are investigated by 195Pt NMR. They form with M = Ba, Sr, La, Ce, Pr, Nd, Sm, Eu, Th and U and in contrast to some pnictide skutterudites they remain metallic independent of the filler ion. Here we show that, consistent with the Korringa theory, the residual shift 195K(T → 0) scales with the density of states N(EF) and with the electronic specific heat coefficient γ. For the heavy filler ions La and Th an unusual 195K(T) dependence was found which might be associated to the effect of dynamic disorder (rattling). For paramagnetic CePt4Ge12 a Curie–Weiss‐like behaviour in both the shift 195K(T) and the bulk susceptibility χ(T) confirms the Ce3+‐4f1‐state at high temperatures. At low temperatures 195K(T) passes through a maximum at around 60 K and saturates below 10 K. This is interpreted being due to an unstable Ce valence, like, e.g. in CeSn3. Further evidence comes from the spin‐lattice relaxation where 195(1/T1) starts to deviate from its low‐temperature linear Korringa‐type of behaviour at around 60 K. We discuss our findings in the context of a dense Kondo system with valence fluctuations. For the van‐Vleck paramagnet SmPt4Ge12 at low‐temperatures, surprisingly, the shift is of the same order as for CePt4Ge12. It also passes through a maximum but at much lower temperatures (∼6 K).