text: ﬂux (in erg cm−2 s−1 Hz−1) over the three month pe- 
  riod. We adopt a lambda cold dark matter cosmology 
  with values of H0 = 71 km s−1 Mpc−1, ΩM = 0.27, 
  and Λ = 0.73. 
  
  We examined submillimeter light curves for all of 
  the SMA blazars, with observations beginning in ap- 
  proximately 2003 (see Figure 1). Typically, the 1mm 
  band is much more well-sampled in comparison to the 
  850m band, but visual inspection reveals that the reg- 
  ularity and quality of observations vary greatly from 
  source to source. Many of the objects exhibit non- 
  periodic variability, either in the form of persistent, 
  low-amplitude ﬂuctuations or higher amplitude ﬂar- 
  ing behavior. 
  Energy Spectral Indices. We derive submillime- 
  ter spectral energy indices from observations quasi- 
  simultaneous with the Fermi observations. To be con- 
  sistent with the use of αγ, we deﬁne spectral energy in- 
  dex as νFν = ν−αS and calculate αS from the average 
  of the energy spectral indices over the corresponding 
  three months. We only calculate αS for the 16 objects 
  (8 BL Lacs and 35 FSRQs) with observations at both 
  1mm and 850µm during this time frame. 