NEW YORK — Magnate Rupert Murdoch’s surprise announcement Thursday that he’s stepping down as leader of his two companies leaves his son Lachlan firmly in line of succession at Fox and the rest of the media empire.

The 92-year-old Australian billionaire’s creation of Fox News Channel has made him an enduring force in American politics. He inherited a newspaper in Adelaide, Australia, from his father in 1952 and eventually built a news and entertainment enterprise dominant in the United States and Britain.

Rupert Murdoch in 2017. Murdoch is stepping down at Fox and News Corp; his son Lachlan will take over as chairman. Photo by Evan Agostini/Invision/AP

Fox said Murdoch would become chairman emeritus of both the news network’s parent company, Fox Corp., and the News Corp. media holdings, effective in November. Lachlan will become News Corp. chairman and continue as chief executive officer of Fox Corp.

Lachlan Murdoch said, “we are grateful that he will serve as chairman emeritus and know he will continue to provide valued counsel.”

Fox News Channel has profoundly influenced television and national politics since its start in 1996, making Murdoch a hero to some and pariah to others. The 24-hour network converted the power and energy of political talk radio to television. Within six years, it outrated CNN and MSNBC, and still does.

But it’s been a rough year for Fox, which was forced to pay $787 million to settle a defamation lawsuit related to its coverage of false claims following the 2020 presidential election. Fox also fired its most popular personality, Tucker Carlson.

Stock in Fox Corp., while positive this year, began to decline early in 2022, due in part to lawsuits and investor anxiety.

Besides Fox News, Rupert Murdoch started the Fox broadcast network, the first to successfully challenge the Big Three of ABC, CBS and NBC, with shows like “The Simpsons.” He owns The Wall Street Journal and the New York Post. He slimmed his corporate holdings with the 2019 sale of many entertainment assets to the Walt Disney Co.

Murdoch has also controlled the New York Post, which, like Fox, has promoted his conservative world view.

Despite Murdoch’s advanced age, Thursday’s announcement took some by surprise.

“I do find it shocking because I figured that Rupert would be around until he couldn’t take a breath,” said writer Claire Atkinson, who’s working on a biography of Murdoch.

In a letter Thursday to staff, Murdoch thundered about elites who have “open contempt for those who are not members of their rarified class.” Murdoch’s letter made it clear he doesn’t consider himself one of them, despite his status as a media executive and his family’s wealth, estimated by Forbes in 2020 at about $19 billion.

He also indicated his retirement won’t include much beach time.

“I can guarantee you that I will be involved every day in the contest of ideas,” he wrote. “Our companies are communities, and I will be an active member of our community. I will be watching our broadcasts with a critical eye, reading our newspapers and websites and books with much interest.”

Murdoch and his family, particularly children James, Lachlan, Elisabeth and Prudence, were said to be the model for the HBO drama “ Succession.”

“Rupert is certainly engineering a cleaner exit than Logan Roy’s departure from WaystarRoyco,” said former CNN president Jon Klein, who consulted on the series. “And he’s leaving behind a lot less of a mess.”

That may be the case — for now, said Murdoch biographer Michael Wolff, who next week is publishing a book, “The End of Fox News.”

“He is 92, and that has taken a toll on him, of course, but the company, too,” Wolff told The Associated Press. “He has remained up until today the singular decision-maker, and he can’t communicate what he wants and people don’t understand what he wants” like they did in the past.

Major changes are unlikely right away under Lachlan Murdoch, who’s largely been running things as CEO for a couple of years.

When Murdoch dies, control of the Fox empire will revert to his four adult children, each of whom has an equal say in the business, Wolff said. “That’s when the real new chapter begins,” he said.

Since Lachlan most closely shares his father’s politically conservative views, Wolff predicted that James Murdoch — known as the more liberal sibling – would eventually take control of Fox News, or that it would be sold.

“It will certainly not exist as the Fox News Channel that we have known and loved, or hated, for the past 25 years,” Wolff said.

Atkinson said that she has talked with people at the company, and they’re saying Murdoch is “fine and as engaged as ever.”

Thursday’s announcement, she said, “is really just Lachlan taking the mantle and saying, ‘now it’s time.’ It’s his company. His company only.”

One of Murdoch’s chief television competitors, Newsmax CEO Chris Ruddy, said that over many decades, no other individual has had as much impact on the media.

“His contributions to the news industry across several continents have been enormous, helping to ensure a balanced and truly free media,” Ruddy said.

Among those who believe Fox has pushed disinformation and is a singular force in worsening the country’s partisan divisions, the reaction to the announcement was, essentially, good riddance.

“They changed how people think of politics in this country, and I think when historians look back on how they changed it, it won’t be a positive look back,” commentator Mike Barnicle said on MSNBC.

While Murdoch never ran for political office, politicians in the United States and Britain anxiously sought his approval. He had a complicated relationship with Donald Trump. Wolff reported in 2018 that Murdoch had called Trump an “idiot,” adding an expletive for emphasis, but Fox News is built with an audience that largely admires Trump.

For decades, Murdoch was one of the most powerful media figures in Britain, a market he entered after buying the tabloid News of the World in 1969. He reinvigorated Britain’s stodgy newspaper scene with sex, scandal and celebrity and helped shake up television with satellite broadcaster Sky.

His clout has waned since the revelation more than a decade ago that employees of the News of the World had eavesdropped on phones and used other underhanded methods to get scoops on celebrities, politicians and royals. News Corp. owns the Times, Sunday Times and Sun newspapers, but News of the World closed and Murdoch sold his 40% stake in Sky when he failed to get complete control of the company.

Fox News went through a series of sexual harassment scandals in the 2010s, which led to top executive Roger Ailes and prime-time personality Bill O’Reilly being pushed out. Murdoch dismissed them as isolated instances that were “largely political because we’re conservative.”

Shares of News Corp. and Fox closed higher Thursday.

AP correspondents Kelvin Chan and Jill Lawless in London, and Brooke Lefferts in New York, contributed to this report.

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