The regional court in the Austrian city of Krems confirmed Fritzl's lawyer, Astrid Wagner, had submitted an early release request.
The lawyer had previously talked about the request on her podcast Plädoyer für Verbrecher (Plea for Criminals).
She argued Fritzl had spent more than 15 years in prison and that the legal requirements for such a move had therefore been met.
"I think he deserves this chance too," she said.
However, Wagner expects that it could still be some time before this happens.
In 1984, Fritzl locked his then 18-year-old daughter in the basement of his house. Over the next 24 years, he raped her thousands of times and fathered seven children with her. One of them died soon after birth.
The wife, who lived on the first floor of the house with the rest of the family, was unaware of any of this, according to the authorities.
The case came to light in 2008 and made headlines around the world.
In March 2009, Fritzl was sentenced to life imprisonment for murder by omission, rape, deprivation of liberty, aggravated coercion, slavery and incest. Fritzl took on a new surname in prison.
An earlier request for early release failed last year. The court cited Fritzl's high level of criminal energy and lack of preparation for a life in freedom.
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