 1075 he was a bitter antagonist of Gregory VII, who finally deposed him on March 3, 1078 and replaced him in his titulus.He took a prominent part in the anti-Gregorian synod of Worms in 1076 and synod of Brixen in 1080 and was repeatedly excommunicated by Gregory VII.Then he joined the obedience of Antipope Clement III and subscribed his bull dated November 4, 1084 as cardinal of S. Clemente.