At the time of Nash's sentencing, Justice Christopher Allan said Nash showed a "complete inability to recognise your risk to young women".
"The way you react to treatment and programmes will determine your release. Your future is in your hands," Justice Allan said.
He said Nash had deliberately targeted young women in public places. "You have little insight into your offending and the effect it has on the victims."
Nash applied for parole and after a hearing earlier this month the Parole Board has released its decision denying him parole, saying he has had 28 individual psychological counselling sessions with limited gain.
The Parole Board said a report in May painted a gloomy picture of Nash, who attempted to minimise his offending.
The report found Nash has poor impulse control and little insight into his offending and his version of the events were "very unreliable". He has not been able to cease his sexually motivated and intimidating predatory behaviour.
The board said Nash appeared to be a poor candidate for psychological interventions.