Upper panel: cumulative observed-companion fraction (ocf, see text) for the double (green), triple (purple), and quadruple (orange) systems as well as the total ocf (black). We also show the values for the double system at 3 and 6 arcsec. Middle and lower panels: calibrated SDSSi magnitude of the 111 companions and differential magnitude with their KOIs. Dashed lines mark the 3 and 6 arcsec positions.