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Mrk 231 is a nearby quasar with an unusually red near-UV-to-opticalcontinuum, generally explained as heavy reddening by dust (e.g., Leighly et al.2014). Yan et al. 2015 proposed that Mrk~231 is a milli-parsec black-holebinary with little intrinsic reddening. We show that if the observed FUVcontinuum is intrinsic, as assumed by Yan et al. 2015, it fails by a factor ofabout 100 in powering the observed strength of the near-infrared emissionlines, and the thermal near and mid-infrared continuum. In contrast, the lineand continuum strengths are typical for a reddened AGN spectral energydistribution. We find that the HeI*/Pbeta ratio is sensitive to the spectralenergy distribution for a one-zone model. If this sensitivity is maintained ingeneral broad-line region models, then this ratio may prove a useful diagnosticfor heavily reddened quasars. Analysis of archival HST STIS and FOC datarevealed evidence that the far-UV continuum emission is resolved on size scalesof ~40 parsecs. The lack of broad absorption lines in the far-UV continuummight be explained if it were not coincident with the central engine. Onepossibility is that it is the central engine continuum reflected from thereceding wind on the far side of the quasar.

The Binary Black Hole Model for Mrk 231 Bites the Dust