Juventus lost to Real Madrid in the 1998 Champions League final.
Arsenal lost the 2006 Champions League final to FC Barcelona. They lost the final 2-0.
Manchester United have only ever lost one Champions League final, against Barcelona in 2009.
Juventus Turin lost to Real Madrid despite of being a favorite.
He played for Arsenal against Barcelona in the 2006 Champions League final, he scored the first goal, but Arsenal eventually lost out 2-1.
Real Madrid have lost the final of the UEFA Champions league 3 times. They did so in 1962, 1964, and 1981.
Three times in the Champions League era: 1993 (to Marseille), 1995 (to Ajax) and 2005 (to Liverpool). They also lost the 1958 European Cup final to Real Madrid.
In the Champions League era, Milan were runners-up in 1993, 1995 and 2005. Pre-CL they also lost the final in 1958.
Barcelona lost the champions league finale twice.
Manchester United have lost the UEFA Champions League final twice. They lost to FC Barcelona in 2009 and 2011.
Arsenal have reached the champion league for the 12 years in a row but they lost the final to Barcelona in the final 2-1 was the score.
Bayer Leverkusen of Germany (2001-2, lost to Real Madrid in the final).