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We study the UV properties of Type I AGN from the ROSAT All-Sky Survey thathave been selected to show unusually soft X-ray continua. We examine a sampleof 54 Seyfert 1 galaxies with detections in both Near-UV and Far-UV bands ofthe Galaxy Evolution Explorer (GALEX) satellite. Our sample is systematicallyfainter in the UV than galaxies studied in similar work by previous authors. Welook for correlations between their UV and X-ray properties as well ascorrelations of these properties with either black hole mass or Eddingtonratio. The shape of the Big Blue Bump(BBB) in the GALEX regime does not appearto correlate with its strength relative to the power law continuum, whichconflicts with results reported by previous authors. The strength of the BBB iscorrelated with the shape of the X-ray continuum, in agreement with previouswork, but the slope of the correlation is different than previously reported.The properties of the accretion disks of Type I AGN in the GALEX regime arerelatively independent of black hole mass and Eddington ratio. We compare ourmeasurements to the predictions of alternative theories for the origin of thesoft excess, but we are unable to distinguish between Comptonization of BBBphotons by a hot plasma and absorption in relativistic winds as the most likelyorigins for the soft X-ray excess.

GALEX Measurements of the Big Blue Bump in Soft X-ray Selected AGN