Rupert Murdoch has lost a legal fight to change his family's trust, which would have let his son Lachlan take control the family's media empire after Murdoch's death.

A Reno probate judge ruled against Rupert Murdoch in his secretive legal battle to alter his family trust and consolidate power for his eldest son, the head of Fox News.

Rupert Murdoch has failed in his attempt to change his family trust in order to centralize control of his media empire in the hands of his son, Lachlan, according to a sealed document.