Abstract
LE and ME spectra of 12 quasars from the EXOSAT data base have been analysed in a search for soft excesses. We have been able to quantify the soft excesses more accurately by using spectral indices for the ME taken from the much more sensitive Ginga observations of the same quasars. Eight quasars show a significant soft excess and the remaining four have upper limits consistent with ubiquity of a soft excess in our sample. We establish variability of the soft excess for three quasars with time-scales consistent with the inner region of an accretion disc around a 10 8 -M ○ . black hole. The luminosity of the soft excess correlates well with other wavebands above M B = −23, but for the most luminous objects the soft excess appears to saturate
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