The prosecution had claimed that Javed Khan raped his step daughter repeatedly between November 2010 and May 2011.
The complaint was lodged after the girl ran away from the house and approached a social worker.
However, Khan's lawyer S M Deshpande argued in the court that the girl implicated Khan as she did not want to stay with the parents.
It was the social worker, an outsider, who had lodged the FIR, he pointed out.
Deshpande also said that it was unbelievable, as contended in the FIR, that the girl was once raped when the mother was sleeping next to her.