One year after
Oliver! (1968) had achieved the only Best Picture win for a movie rated 'G' by the Motion Picture Association of America (MPAA), at this Academy Awards presentation
Perdidos na Noite (1969) became the only film rated 'X' by the MPAA to win the Best Picture Oscar, although the film's rating was later downgraded to 'R" after the organization redefined its rating criteria. The only other such X-rated film to be nominated for Best Picture would be
Laranja Mecânica (1971) two Oscarcasts later, that movie also later downgraded to an 'R' but in that case due to editing cuts made to the film. The MPAA's 'X' rating was abandoned in 1990 in favor of the 'NC-17' rating, which has been applied to numerous Oscar-nominated films since.
