Using121Sb Moessbauer spectroscopy information concerning both ionicity and valence stale of the intercalate in ternary graphite intercalation compounds (GIC) can be obtained. It has been proved that the major portion of antimony in the SbCl5/MCl3-GIC has the valence state of Sb(V) whereas oxidation of the graphite is to be expected only to an insignificant extent. Two different antimony phases of a neutral and a negatively charged species were shown to exist by evaluation of the spectra in the Sb(V) region. In comparison with the binary SbCl5-GIC the changes of the isomer shift may be a consequence of intermolecidar interactions with the trichlorides. These changes are in accordance with Pauling's electronegativities. Assuming the existence of polymeric anions consisting of the species SbCl5, SbCl6−and MCl3in the interlaminary spacings an interpretation of the spectra is given. For the ternary GIC the following structure is suggested