The formation of the Seyfert continuum
  We discuss recent results on the Seyfert spectral variability. Their observed high energy variability is generally consistent with X-ray spectral slop fluctuations produced by change of the soft photon luminosity in the sense that spectra soften when the UV flux increases. These behaviors strongly favor a thermal origin for the X-ray emission in these objects. We present the case of NGC 7469, showing the results of the reanalysis of the simultaneous IUE/XTE observations of this object using a realistic thermal Comptonization model to fit the continuum instead of the simple power law approximation adopted in the past. 
P. O. Petrucci