We report vibrationally resolved results on 2a 2 u - 1 photoionization of C 6 F 6 . Vibrational branching ratios are determined for the ring breathing mode by measuring dispersed fluorescence spectra of the C 6 F 6 + (B 2 A 2 u ->X 2 E 1 g ) transition. Data are presented in the excitation energy range from 20 to 35 eV, and the vibrational branching ratios show a striking departure from Franck-Condon behavior from 20 to 25 eV. This deviation is attributed to a shape resonance.