Black hole mass as a function of X-ray luminosity for our measured radio luminosity (L_R = 6.34 × 10²⁷ erg s^-1) as predicted by the FP from Körding et al. (2006) (solid lines) and Plotkin et al. (2012) (dashed lines). The gray shaded areas indicate the 1σ uncertainties of the relations. The horizontal lines mark the predicted masses for different assumptions on the radiative efficiency η and the accretion efficiency ϵ. The vertical dotted line marks the upper limit for the X-ray luminosity from Hannikainen et al. (2005).