Relative partial photoionization cross sections and photoelectron branching ratios have been measured for the valence bands of the bis-η 5-cyclopentadienyl compounds of vanadium, chromium, cobalt and nickel over the photon energy range 20 to 80 or 100 eV. The d bands show cross section features attributable to 3d resonant photoemission in the vicinity of the 3p → 3d giant resonance absorption. These features are stronger for V and Cr than for Co and Ni. Other intensity maxima are attributed to shape resonances in f ionization channels for the a 1′ and e 2′ ionizations those for the a 1′ being stronger than those for the e 2′ bands. The 2 e 1″ bands of Co(η-C 5H 5) 2 and Ni(η-C 5H 5) 2 show particularly strong shape resonances. Evidence is presented for d orbitals covalency in the 1 e 1″ orbitals. Previous assignments for the a 1′ ionizations are confirmed.