Top panel: color comparison of g−r between PTF11mnb, SN 2005bf, SN Ib iPTF13bvn (Fremling et al. 2016), and SN IIb 2011dh (Ergon et al. 2014, 2015). The first two SNe reach a red peak in the color, which coincides with the early peak in their light curves (see bottom panel). Then their g−r becomes bluer reaching a minimum when the main peak of the light curves occurs. Thereafter, they rapidly evolve to redder colors. PTF11mnb also shows a shallow trend to the blue after ~100 d, when the light curves are flatter (see bottom panel) and when SN 2005bf was not observed. iPTf13bvn and SN 2011dh evolve very differently, reaching a g−r minimum at peak magnitude, followed by a linear trend to the red and a final flatter color after ~30 d. Bottom panel: absolute g- and r-band light curves of PTF11mnb and SN 2005bf, plotted as a reference for the various phases of the color evolution.