• The person said she was “half-asleep” when they had sex, which is very different to being asleep.
• The condom which was presented as evidence didn’t contain DNA of Assange or of the person he alledgedly raped.
• The person who accused him once wrote an article "“The 7 Steps To Revenge against men who dump you.” False rape accusations was one of the steps.
• Of the two women, has to this day kept on refusing to sign a statement which contains that he raped her
• Sweden has very strict laws about the identity of people whoi’re accused of crimes. One of the two women used to work in the newspaper Expressen, where - contrary to Swedish law - his identity was leaked. The same newspaper also published Assange testimony to the police (in which he said he was afraid it would be leaked to that newspaper).

If you want to know more: I’d suggest starting with this article and the sources it quotes.