Rupert Murdoch’s attempt to give his eldest son control of his family media empire has been blocked by a US court after a lengthy legal battle with three of his other children.

The real-life “Succession” courtroom tussle saw the 93-year-old media mogul fail in his bid to change his family trust, which now gives his four oldest children equal voting power to control the group behind News Corp and Fox News after his death.

A court commissioner ruled that Mr Murdoch and his son Lachlan – the head of Fox News and News Corp – had acted in “bad faith” and called their efforts a “carefully crafted charade” designed to “permanently cement” Lachlan’s control, according to a sealed document obtained at the weekend by The New York Times.

The conflict over the family trust is not thought to be centred around money, as Mr Murdoch is not seeking to diminish any of his children’s financial inheritance.

Instead, it would have changed the voting power of his less-conservative children and is thought to have been a move to cement a right-wing agenda across his media empire.

Lawyer Adam Streisand, acting on behalf of Mr Murdoch, told the newspaper they planned to appeal the decision handed down by a court in Nevada.

Prudence, Elisabeth and James, said in a statement given to the Times: “We welcome Commissioner Gorman’s decision and hope that we can move beyond this litigation to focus on strengthening and rebuilding relationships among all family members.”

The legal case reportedly began when the Murdoch children watched an episode of HBO drama Succession, which sees the patriarch, played by Scottish actor Brian Cox, leave family and business in chaos after his death.

The episode led Elisabeth’s representative to the trust to write a “‘Succession’ memo” to prevent a repeat in real life, according to the New York Times.

Mr Murdoch established the family trust in 2006, which sees him retain control over the business until his death when voting shares will be distributed equally among his four oldest children.

The media titan, who has been married five times, also has two younger children, Grace and Chloe, who do not have any voting rights under the agreement but have an equal financial stake.

Mr Murdoch had argued that to preserve his businesses’ commercial value for all his heirs, the trust should be changed to allow Lachlan Murdoch to maintain Fox News’ conservative slant.

James and Elisabeth Murdoch are both known to have less-conservative political views than their father or brother.

The case has thrown the spotlight on deep rifts in the billionaire Murdoch family and opened questions over the future of the media organisation.

The empire spans influential media outlets worldwide, including Fox News, The New York Post, The Wall Street Journal in America, and newspapers The Sun and The Times in the UK.

Even after the court ruling, the battle could rage on, with the losing party free to challenge the determination.

If all legal attempts fail, Mr Murdoch and Lachlan are also said to be able to pursue other ways to consolidate Lachlan’s power, for example, with the eldest son seeking to buy out his siblings’ stake in the company.

Representatives for Mr Murdoch have been contacted for comment.