Most people believe "A Clockwork Orange" was banned for 30 years, this is not the case Stanley Kubrick himself withdrew the film from circulation and refused licenses for home media and TV because he felt his film was under appreciated and did not want it butchered for television or exposed to further, as he saw it, unjustified criticism.
In 1971 it met with mixed reviews and like Kubricks later works (Especially the Shining) was compared unfavourably to it's source material.(Which is a highly disturbing read.)
As soon as Kubrick died in 1999, the film was approved for release on VHS and DVD (R rating in the USA 18 rating in the UK) and was broadcast uncut on Sky TV in 2001 largely to a disappointed audience who could not see what all the fuss was about.